v3.26.1
Shareholder Report, Holdings (Details)
Feb. 28, 2026
C000013178 | Not Rated  
Holdings [Line Items]  
Percent of Total Investments 8.10%
C000013178 | BB  
Holdings [Line Items]  
Percent of Total Investments 1.10%
C000013178 | BBB  
Holdings [Line Items]  
Percent of Total Investments 4.10%
C000013178 | A  
Holdings [Line Items]  
Percent of Total Investments 16.80%
C000013178 | AA  
Holdings [Line Items]  
Percent of Total Investments 60.60%
C000013178 | AAA  
Holdings [Line Items]  
Percent of Total Investments 9.30%
C000013178 | Industry Other Line  
Holdings [Line Items]  
Percent of Total Investments 6.60%
C000013178 | Other Revenue  
Holdings [Line Items]  
Percent of Total Investments 4.30%
C000013178 | Electric Utilities  
Holdings [Line Items]  
Percent of Total Investments 5.60%
C000013178 | Industrial Development Revenue  
Holdings [Line Items]  
Percent of Total Investments 5.90%
C000013178 | Special Tax Revenue  
Holdings [Line Items]  
Percent of Total Investments 6.00%
C000013178 | Education  
Holdings [Line Items]  
Percent of Total Investments 6.70%
C000013178 | Housing  
Holdings [Line Items]  
Percent of Total Investments 9.90%
C000013178 | Hospital  
Holdings [Line Items]  
Percent of Total Investments 10.80%
C000013178 | Transportation  
Holdings [Line Items]  
Percent of Total Investments 13.00%
C000013178 | General Obligations  
Holdings [Line Items]  
Percent of Total Investments 14.40%
C000013178 | Water and Sewer  
Holdings [Line Items]  
Percent of Total Investments 16.80%
C000013180 | Not Rated  
Holdings [Line Items]  
Percent of Total Investments 8.10%
C000013180 | BB  
Holdings [Line Items]  
Percent of Total Investments 1.10%
C000013180 | BBB  
Holdings [Line Items]  
Percent of Total Investments 4.10%
C000013180 | A  
Holdings [Line Items]  
Percent of Total Investments 16.80%
C000013180 | AA  
Holdings [Line Items]  
Percent of Total Investments 60.60%
C000013180 | AAA  
Holdings [Line Items]  
Percent of Total Investments 9.30%
C000013180 | Industry Other Line  
Holdings [Line Items]  
Percent of Total Investments 6.60%
C000013180 | Other Revenue  
Holdings [Line Items]  
Percent of Total Investments 4.30%
C000013180 | Electric Utilities  
Holdings [Line Items]  
Percent of Total Investments 5.60%
C000013180 | Industrial Development Revenue  
Holdings [Line Items]  
Percent of Total Investments 5.90%
C000013180 | Special Tax Revenue  
Holdings [Line Items]  
Percent of Total Investments 6.00%
C000013180 | Education  
Holdings [Line Items]  
Percent of Total Investments 6.70%
C000013180 | Housing  
Holdings [Line Items]  
Percent of Total Investments 9.90%
C000013180 | Hospital  
Holdings [Line Items]  
Percent of Total Investments 10.80%
C000013180 | Transportation  
Holdings [Line Items]  
Percent of Total Investments 13.00%
C000013180 | General Obligations  
Holdings [Line Items]  
Percent of Total Investments 14.40%
C000013180 | Water and Sewer  
Holdings [Line Items]  
Percent of Total Investments 16.80%
C000063956 | Not Rated  
Holdings [Line Items]  
Percent of Total Investments 8.10%
C000063956 | BB  
Holdings [Line Items]  
Percent of Total Investments 1.10%
C000063956 | BBB  
Holdings [Line Items]  
Percent of Total Investments 4.10%
C000063956 | A  
Holdings [Line Items]  
Percent of Total Investments 16.80%
C000063956 | AA  
Holdings [Line Items]  
Percent of Total Investments 60.60%
C000063956 | AAA  
Holdings [Line Items]  
Percent of Total Investments 9.30%
C000063956 | Industry Other Line  
Holdings [Line Items]  
Percent of Total Investments 6.60%
C000063956 | Other Revenue  
Holdings [Line Items]  
Percent of Total Investments 4.30%
C000063956 | Electric Utilities  
Holdings [Line Items]  
Percent of Total Investments 5.60%
C000063956 | Industrial Development Revenue  
Holdings [Line Items]  
Percent of Total Investments 5.90%
C000063956 | Special Tax Revenue  
Holdings [Line Items]  
Percent of Total Investments 6.00%
C000063956 | Education  
Holdings [Line Items]  
Percent of Total Investments 6.70%
C000063956 | Housing  
Holdings [Line Items]  
Percent of Total Investments 9.90%
C000063956 | Hospital  
Holdings [Line Items]  
Percent of Total Investments 10.80%
C000063956 | Transportation  
Holdings [Line Items]  
Percent of Total Investments 13.00%
C000063956 | General Obligations  
Holdings [Line Items]  
Percent of Total Investments 14.40%
C000063956 | Water and Sewer  
Holdings [Line Items]  
Percent of Total Investments 16.80%
C000013104 | Not Rated  
Holdings [Line Items]  
Percent of Total Investments 6.80%
C000013104 | BB  
Holdings [Line Items]  
Percent of Total Investments 2.50%
C000013104 | BBB  
Holdings [Line Items]  
Percent of Total Investments 6.20%
C000013104 | A  
Holdings [Line Items]  
Percent of Total Investments 21.30%
C000013104 | AA  
Holdings [Line Items]  
Percent of Total Investments 42.50%
C000013104 | AAA  
Holdings [Line Items]  
Percent of Total Investments 20.70%
C000013104 | Industry Other Line  
Holdings [Line Items]  
Percent of Total Investments 8.80%
C000013104 | Special Tax Revenue  
Holdings [Line Items]  
Percent of Total Investments 7.00%
C000013104 | Education  
Holdings [Line Items]  
Percent of Total Investments 7.90%
C000013104 | Housing  
Holdings [Line Items]  
Percent of Total Investments 14.80%
C000013104 | Hospital  
Holdings [Line Items]  
Percent of Total Investments 19.10%
C000013104 | Transportation  
Holdings [Line Items]  
Percent of Total Investments 12.80%
C000013104 | General Obligations  
Holdings [Line Items]  
Percent of Total Investments 21.50%
C000013104 | Senior Living/Life Care  
Holdings [Line Items]  
Percent of Total Investments 3.10%
C000013104 | Lease Rev./Cert. of Participation  
Holdings [Line Items]  
Percent of Total Investments 5.00%
C000013106 | Not Rated  
Holdings [Line Items]  
Percent of Total Investments 6.80%
C000013106 | BB  
Holdings [Line Items]  
Percent of Total Investments 2.50%
C000013106 | BBB  
Holdings [Line Items]  
Percent of Total Investments 6.20%
C000013106 | A  
Holdings [Line Items]  
Percent of Total Investments 21.30%
C000013106 | AA  
Holdings [Line Items]  
Percent of Total Investments 42.50%
C000013106 | AAA  
Holdings [Line Items]  
Percent of Total Investments 20.70%
C000013106 | Industry Other Line  
Holdings [Line Items]  
Percent of Total Investments 8.80%
C000013106 | Special Tax Revenue  
Holdings [Line Items]  
Percent of Total Investments 7.00%
C000013106 | Education  
Holdings [Line Items]  
Percent of Total Investments 7.90%
C000013106 | Housing  
Holdings [Line Items]  
Percent of Total Investments 14.80%
C000013106 | Hospital  
Holdings [Line Items]  
Percent of Total Investments 19.10%
C000013106 | Transportation  
Holdings [Line Items]  
Percent of Total Investments 12.80%
C000013106 | General Obligations  
Holdings [Line Items]  
Percent of Total Investments 21.50%
C000013106 | Senior Living/Life Care  
Holdings [Line Items]  
Percent of Total Investments 3.10%
C000013106 | Lease Rev./Cert. of Participation  
Holdings [Line Items]  
Percent of Total Investments 5.00%
C000063947 | Not Rated  
Holdings [Line Items]  
Percent of Total Investments 6.80%
C000063947 | BB  
Holdings [Line Items]  
Percent of Total Investments 2.50%
C000063947 | BBB  
Holdings [Line Items]  
Percent of Total Investments 6.20%
C000063947 | A  
Holdings [Line Items]  
Percent of Total Investments 21.30%
C000063947 | AA  
Holdings [Line Items]  
Percent of Total Investments 42.50%
C000063947 | AAA  
Holdings [Line Items]  
Percent of Total Investments 20.70%
C000063947 | Industry Other Line  
Holdings [Line Items]  
Percent of Total Investments 8.80%
C000063947 | Special Tax Revenue  
Holdings [Line Items]  
Percent of Total Investments 7.00%
C000063947 | Education  
Holdings [Line Items]  
Percent of Total Investments 7.90%
C000063947 | Housing  
Holdings [Line Items]  
Percent of Total Investments 14.80%
C000063947 | Hospital  
Holdings [Line Items]  
Percent of Total Investments 19.10%
C000063947 | Transportation  
Holdings [Line Items]  
Percent of Total Investments 12.80%
C000063947 | General Obligations  
Holdings [Line Items]  
Percent of Total Investments 21.50%
C000063947 | Senior Living/Life Care  
Holdings [Line Items]  
Percent of Total Investments 3.10%
C000063947 | Lease Rev./Cert. of Participation  
Holdings [Line Items]  
Percent of Total Investments 5.00%
C000013120 | Not Rated  
Holdings [Line Items]  
Percent of Total Investments 5.40%
C000013120 | BB  
Holdings [Line Items]  
Percent of Total Investments 2.40%
C000013120 | BBB  
Holdings [Line Items]  
Percent of Total Investments 4.60%
C000013120 | A  
Holdings [Line Items]  
Percent of Total Investments 18.30%
C000013120 | AA  
Holdings [Line Items]  
Percent of Total Investments 68.00%
C000013120 | AAA  
Holdings [Line Items]  
Percent of Total Investments 1.30%
C000013120 | Industry Other Line  
Holdings [Line Items]  
Percent of Total Investments 9.70%
C000013120 | Special Tax Revenue  
Holdings [Line Items]  
Percent of Total Investments 4.20%
C000013120 | Education  
Holdings [Line Items]  
Percent of Total Investments 8.90%
C000013120 | Housing  
Holdings [Line Items]  
Percent of Total Investments 4.30%
C000013120 | Hospital  
Holdings [Line Items]  
Percent of Total Investments 11.80%
C000013120 | Transportation  
Holdings [Line Items]  
Percent of Total Investments 6.90%
C000013120 | General Obligations  
Holdings [Line Items]  
Percent of Total Investments 29.00%
C000013120 | Water and Sewer  
Holdings [Line Items]  
Percent of Total Investments 7.10%
C000013120 | Senior Living/Life Care  
Holdings [Line Items]  
Percent of Total Investments 5.40%
C000013120 | Lease Rev./Cert. of Participation  
Holdings [Line Items]  
Percent of Total Investments 12.70%
C000013122 | Not Rated  
Holdings [Line Items]  
Percent of Total Investments 5.40%
C000013122 | BB  
Holdings [Line Items]  
Percent of Total Investments 2.40%
C000013122 | BBB  
Holdings [Line Items]  
Percent of Total Investments 4.60%
C000013122 | A  
Holdings [Line Items]  
Percent of Total Investments 18.30%
C000013122 | AA  
Holdings [Line Items]  
Percent of Total Investments 68.00%
C000013122 | AAA  
Holdings [Line Items]  
Percent of Total Investments 1.30%
C000013122 | Industry Other Line  
Holdings [Line Items]  
Percent of Total Investments 9.70%
C000013122 | Special Tax Revenue  
Holdings [Line Items]  
Percent of Total Investments 4.20%
C000013122 | Education  
Holdings [Line Items]  
Percent of Total Investments 8.90%
C000013122 | Housing  
Holdings [Line Items]  
Percent of Total Investments 4.30%
C000013122 | Hospital  
Holdings [Line Items]  
Percent of Total Investments 11.80%
C000013122 | Transportation  
Holdings [Line Items]  
Percent of Total Investments 6.90%
C000013122 | General Obligations  
Holdings [Line Items]  
Percent of Total Investments 29.00%
C000013122 | Water and Sewer  
Holdings [Line Items]  
Percent of Total Investments 7.10%
C000013122 | Senior Living/Life Care  
Holdings [Line Items]  
Percent of Total Investments 5.40%
C000013122 | Lease Rev./Cert. of Participation  
Holdings [Line Items]  
Percent of Total Investments 12.70%
C000092719 | Not Rated  
Holdings [Line Items]  
Percent of Total Investments 5.40%
C000092719 | BB  
Holdings [Line Items]  
Percent of Total Investments 2.40%
C000092719 | BBB  
Holdings [Line Items]  
Percent of Total Investments 4.60%
C000092719 | A  
Holdings [Line Items]  
Percent of Total Investments 18.30%
C000092719 | AA  
Holdings [Line Items]  
Percent of Total Investments 68.00%
C000092719 | AAA  
Holdings [Line Items]  
Percent of Total Investments 1.30%
C000092719 | Industry Other Line  
Holdings [Line Items]  
Percent of Total Investments 9.70%
C000092719 | Special Tax Revenue  
Holdings [Line Items]  
Percent of Total Investments 4.20%
C000092719 | Education  
Holdings [Line Items]  
Percent of Total Investments 8.90%
C000092719 | Housing  
Holdings [Line Items]  
Percent of Total Investments 4.30%
C000092719 | Hospital  
Holdings [Line Items]  
Percent of Total Investments 11.80%
C000092719 | Transportation  
Holdings [Line Items]  
Percent of Total Investments 6.90%
C000092719 | General Obligations  
Holdings [Line Items]  
Percent of Total Investments 29.00%
C000092719 | Water and Sewer  
Holdings [Line Items]  
Percent of Total Investments 7.10%
C000092719 | Senior Living/Life Care  
Holdings [Line Items]  
Percent of Total Investments 5.40%
C000092719 | Lease Rev./Cert. of Participation  
Holdings [Line Items]  
Percent of Total Investments 12.70%
C000013136 | Not Rated  
Holdings [Line Items]  
Percent of Total Investments 5.20%
C000013136 | BB  
Holdings [Line Items]  
Percent of Total Investments 0.20%
C000013136 | BBB  
Holdings [Line Items]  
Percent of Total Investments 7.00%
C000013136 | A  
Holdings [Line Items]  
Percent of Total Investments 5.10%
C000013136 | AA  
Holdings [Line Items]  
Percent of Total Investments 67.70%
C000013136 | AAA  
Holdings [Line Items]  
Percent of Total Investments 14.80%
C000013136 | Industry Other Line  
Holdings [Line Items]  
Percent of Total Investments 6.40%
C000013136 | Electric Utilities  
Holdings [Line Items]  
Percent of Total Investments 3.90%
C000013136 | Education  
Holdings [Line Items]  
Percent of Total Investments 10.40%
C000013136 | Housing  
Holdings [Line Items]  
Percent of Total Investments 6.60%
C000013136 | Hospital  
Holdings [Line Items]  
Percent of Total Investments 16.00%
C000013136 | Transportation  
Holdings [Line Items]  
Percent of Total Investments 11.40%
C000013136 | General Obligations  
Holdings [Line Items]  
Percent of Total Investments 4.80%
C000013136 | Water and Sewer  
Holdings [Line Items]  
Percent of Total Investments 19.30%
C000013136 | Senior Living/Life Care  
Holdings [Line Items]  
Percent of Total Investments 7.80%
C000013136 | Lease Rev./Cert. of Participation  
Holdings [Line Items]  
Percent of Total Investments 13.40%
C000013138 | Not Rated  
Holdings [Line Items]  
Percent of Total Investments 5.20%
C000013138 | BB  
Holdings [Line Items]  
Percent of Total Investments 0.20%
C000013138 | BBB  
Holdings [Line Items]  
Percent of Total Investments 7.00%
C000013138 | A  
Holdings [Line Items]  
Percent of Total Investments 5.10%
C000013138 | AA  
Holdings [Line Items]  
Percent of Total Investments 67.70%
C000013138 | AAA  
Holdings [Line Items]  
Percent of Total Investments 14.80%
C000013138 | Industry Other Line  
Holdings [Line Items]  
Percent of Total Investments 6.40%
C000013138 | Electric Utilities  
Holdings [Line Items]  
Percent of Total Investments 3.90%
C000013138 | Education  
Holdings [Line Items]  
Percent of Total Investments 10.40%
C000013138 | Housing  
Holdings [Line Items]  
Percent of Total Investments 6.60%
C000013138 | Hospital  
Holdings [Line Items]  
Percent of Total Investments 16.00%
C000013138 | Transportation  
Holdings [Line Items]  
Percent of Total Investments 11.40%
C000013138 | General Obligations  
Holdings [Line Items]  
Percent of Total Investments 4.80%
C000013138 | Water and Sewer  
Holdings [Line Items]  
Percent of Total Investments 19.30%
C000013138 | Senior Living/Life Care  
Holdings [Line Items]  
Percent of Total Investments 7.80%
C000013138 | Lease Rev./Cert. of Participation  
Holdings [Line Items]  
Percent of Total Investments 13.40%
C000063950 | Not Rated  
Holdings [Line Items]  
Percent of Total Investments 5.20%
C000063950 | BB  
Holdings [Line Items]  
Percent of Total Investments 0.20%
C000063950 | BBB  
Holdings [Line Items]  
Percent of Total Investments 7.00%
C000063950 | A  
Holdings [Line Items]  
Percent of Total Investments 5.10%
C000063950 | AA  
Holdings [Line Items]  
Percent of Total Investments 67.70%
C000063950 | AAA  
Holdings [Line Items]  
Percent of Total Investments 14.80%
C000063950 | Industry Other Line  
Holdings [Line Items]  
Percent of Total Investments 6.40%
C000063950 | Electric Utilities  
Holdings [Line Items]  
Percent of Total Investments 3.90%
C000063950 | Education  
Holdings [Line Items]  
Percent of Total Investments 10.40%
C000063950 | Housing  
Holdings [Line Items]  
Percent of Total Investments 6.60%
C000063950 | Hospital  
Holdings [Line Items]  
Percent of Total Investments 16.00%
C000063950 | Transportation  
Holdings [Line Items]  
Percent of Total Investments 11.40%
C000063950 | General Obligations  
Holdings [Line Items]  
Percent of Total Investments 4.80%
C000063950 | Water and Sewer  
Holdings [Line Items]  
Percent of Total Investments 19.30%
C000063950 | Senior Living/Life Care  
Holdings [Line Items]  
Percent of Total Investments 7.80%
C000063950 | Lease Rev./Cert. of Participation  
Holdings [Line Items]  
Percent of Total Investments 13.40%
C000013142 | Not Rated  
Holdings [Line Items]  
Percent of Total Investments 2.60%
C000013142 | BB  
Holdings [Line Items]  
Percent of Total Investments 1.70%
C000013142 | BBB  
Holdings [Line Items]  
Percent of Total Investments 2.70%
C000013142 | A  
Holdings [Line Items]  
Percent of Total Investments 5.80%
C000013142 | AA  
Holdings [Line Items]  
Percent of Total Investments 80.10%
C000013142 | AAA  
Holdings [Line Items]  
Percent of Total Investments 7.10%
C000013142 | Industry Other Line  
Holdings [Line Items]  
Percent of Total Investments 4.40%
C000013142 | Electric Utilities  
Holdings [Line Items]  
Percent of Total Investments 4.50%
C000013142 | Special Tax Revenue  
Holdings [Line Items]  
Percent of Total Investments 4.30%
C000013142 | Education  
Holdings [Line Items]  
Percent of Total Investments 7.50%
C000013142 | Housing  
Holdings [Line Items]  
Percent of Total Investments 5.20%
C000013142 | Hospital  
Holdings [Line Items]  
Percent of Total Investments 12.70%
C000013142 | Transportation  
Holdings [Line Items]  
Percent of Total Investments 4.40%
C000013142 | General Obligations  
Holdings [Line Items]  
Percent of Total Investments 46.70%
C000013142 | Water and Sewer  
Holdings [Line Items]  
Percent of Total Investments 10.30%
C000013144 | Not Rated  
Holdings [Line Items]  
Percent of Total Investments 2.60%
C000013144 | BB  
Holdings [Line Items]  
Percent of Total Investments 1.70%
C000013144 | BBB  
Holdings [Line Items]  
Percent of Total Investments 2.70%
C000013144 | A  
Holdings [Line Items]  
Percent of Total Investments 5.80%
C000013144 | AA  
Holdings [Line Items]  
Percent of Total Investments 80.10%
C000013144 | AAA  
Holdings [Line Items]  
Percent of Total Investments 7.10%
C000013144 | Industry Other Line  
Holdings [Line Items]  
Percent of Total Investments 4.40%
C000013144 | Electric Utilities  
Holdings [Line Items]  
Percent of Total Investments 4.50%
C000013144 | Special Tax Revenue  
Holdings [Line Items]  
Percent of Total Investments 4.30%
C000013144 | Education  
Holdings [Line Items]  
Percent of Total Investments 7.50%
C000013144 | Housing  
Holdings [Line Items]  
Percent of Total Investments 5.20%
C000013144 | Hospital  
Holdings [Line Items]  
Percent of Total Investments 12.70%
C000013144 | Transportation  
Holdings [Line Items]  
Percent of Total Investments 4.40%
C000013144 | General Obligations  
Holdings [Line Items]  
Percent of Total Investments 46.70%
C000013144 | Water and Sewer  
Holdings [Line Items]  
Percent of Total Investments 10.30%
C000092722 | Not Rated  
Holdings [Line Items]  
Percent of Total Investments 2.60%
C000092722 | BB  
Holdings [Line Items]  
Percent of Total Investments 1.70%
C000092722 | BBB  
Holdings [Line Items]  
Percent of Total Investments 2.70%
C000092722 | A  
Holdings [Line Items]  
Percent of Total Investments 5.80%
C000092722 | AA  
Holdings [Line Items]  
Percent of Total Investments 80.10%
C000092722 | AAA  
Holdings [Line Items]  
Percent of Total Investments 7.10%
C000092722 | Industry Other Line  
Holdings [Line Items]  
Percent of Total Investments 4.40%
C000092722 | Electric Utilities  
Holdings [Line Items]  
Percent of Total Investments 4.50%
C000092722 | Special Tax Revenue  
Holdings [Line Items]  
Percent of Total Investments 4.30%
C000092722 | Education  
Holdings [Line Items]  
Percent of Total Investments 7.50%
C000092722 | Housing  
Holdings [Line Items]  
Percent of Total Investments 5.20%
C000092722 | Hospital  
Holdings [Line Items]  
Percent of Total Investments 12.70%
C000092722 | Transportation  
Holdings [Line Items]  
Percent of Total Investments 4.40%
C000092722 | General Obligations  
Holdings [Line Items]  
Percent of Total Investments 46.70%
C000092722 | Water and Sewer  
Holdings [Line Items]  
Percent of Total Investments 10.30%
C000013151 | Not Rated  
Holdings [Line Items]  
Percent of Total Investments 7.80%
C000013151 | BB  
Holdings [Line Items]  
Percent of Total Investments 2.80%
C000013151 | BBB  
Holdings [Line Items]  
Percent of Total Investments 4.70%
C000013151 | A  
Holdings [Line Items]  
Percent of Total Investments 26.70%
C000013151 | AA  
Holdings [Line Items]  
Percent of Total Investments 47.60%
C000013151 | AAA  
Holdings [Line Items]  
Percent of Total Investments 10.40%
C000013151 | Industry Other Line  
Holdings [Line Items]  
Percent of Total Investments 4.50%
C000013151 | Electric Utilities  
Holdings [Line Items]  
Percent of Total Investments 11.40%
C000013151 | Education  
Holdings [Line Items]  
Percent of Total Investments 6.10%
C000013151 | Housing  
Holdings [Line Items]  
Percent of Total Investments 8.00%
C000013151 | Hospital  
Holdings [Line Items]  
Percent of Total Investments 14.40%
C000013151 | Transportation  
Holdings [Line Items]  
Percent of Total Investments 4.40%
C000013151 | General Obligations  
Holdings [Line Items]  
Percent of Total Investments 16.10%
C000013151 | Water and Sewer  
Holdings [Line Items]  
Percent of Total Investments 11.00%
C000013151 | Senior Living/Life Care  
Holdings [Line Items]  
Percent of Total Investments 4.20%
C000013151 | Lease Rev./Cert. of Participation  
Holdings [Line Items]  
Percent of Total Investments 6.60%
C000013151 | Short-Term Investments  
Holdings [Line Items]  
Percent of Total Investments 13.30%
C000013153 | Not Rated  
Holdings [Line Items]  
Percent of Total Investments 7.80%
C000013153 | BB  
Holdings [Line Items]  
Percent of Total Investments 2.80%
C000013153 | BBB  
Holdings [Line Items]  
Percent of Total Investments 4.70%
C000013153 | A  
Holdings [Line Items]  
Percent of Total Investments 26.70%
C000013153 | AA  
Holdings [Line Items]  
Percent of Total Investments 47.60%
C000013153 | AAA  
Holdings [Line Items]  
Percent of Total Investments 10.40%
C000013153 | Industry Other Line  
Holdings [Line Items]  
Percent of Total Investments 4.50%
C000013153 | Electric Utilities  
Holdings [Line Items]  
Percent of Total Investments 11.40%
C000013153 | Education  
Holdings [Line Items]  
Percent of Total Investments 6.10%
C000013153 | Housing  
Holdings [Line Items]  
Percent of Total Investments 8.00%
C000013153 | Hospital  
Holdings [Line Items]  
Percent of Total Investments 14.40%
C000013153 | Transportation  
Holdings [Line Items]  
Percent of Total Investments 4.40%
C000013153 | General Obligations  
Holdings [Line Items]  
Percent of Total Investments 16.10%
C000013153 | Water and Sewer  
Holdings [Line Items]  
Percent of Total Investments 11.00%
C000013153 | Senior Living/Life Care  
Holdings [Line Items]  
Percent of Total Investments 4.20%
C000013153 | Lease Rev./Cert. of Participation  
Holdings [Line Items]  
Percent of Total Investments 6.60%
C000013153 | Short-Term Investments  
Holdings [Line Items]  
Percent of Total Investments 13.30%
C000063952 | Not Rated  
Holdings [Line Items]  
Percent of Total Investments 7.80%
C000063952 | BB  
Holdings [Line Items]  
Percent of Total Investments 2.80%
C000063952 | BBB  
Holdings [Line Items]  
Percent of Total Investments 4.70%
C000063952 | A  
Holdings [Line Items]  
Percent of Total Investments 26.70%
C000063952 | AA  
Holdings [Line Items]  
Percent of Total Investments 47.60%
C000063952 | AAA  
Holdings [Line Items]  
Percent of Total Investments 10.40%
C000063952 | Industry Other Line  
Holdings [Line Items]  
Percent of Total Investments 4.50%
C000063952 | Electric Utilities  
Holdings [Line Items]  
Percent of Total Investments 11.40%
C000063952 | Education  
Holdings [Line Items]  
Percent of Total Investments 6.10%
C000063952 | Housing  
Holdings [Line Items]  
Percent of Total Investments 8.00%
C000063952 | Hospital  
Holdings [Line Items]  
Percent of Total Investments 14.40%
C000063952 | Transportation  
Holdings [Line Items]  
Percent of Total Investments 4.40%
C000063952 | General Obligations  
Holdings [Line Items]  
Percent of Total Investments 16.10%
C000063952 | Water and Sewer  
Holdings [Line Items]  
Percent of Total Investments 11.00%
C000063952 | Senior Living/Life Care  
Holdings [Line Items]  
Percent of Total Investments 4.20%
C000063952 | Lease Rev./Cert. of Participation  
Holdings [Line Items]  
Percent of Total Investments 6.60%
C000063952 | Short-Term Investments  
Holdings [Line Items]  
Percent of Total Investments 13.30%
C000013157 | Not Rated  
Holdings [Line Items]  
Percent of Total Investments 8.20%
C000013157 | BB  
Holdings [Line Items]  
Percent of Total Investments 3.00%
C000013157 | BBB  
Holdings [Line Items]  
Percent of Total Investments 6.70%
C000013157 | A  
Holdings [Line Items]  
Percent of Total Investments 5.20%
C000013157 | AA  
Holdings [Line Items]  
Percent of Total Investments 57.70%
C000013157 | AAA  
Holdings [Line Items]  
Percent of Total Investments 18.10%
C000013157 | B  
Holdings [Line Items]  
Percent of Total Investments 1.10%
C000013157 | Industry Other Line  
Holdings [Line Items]  
Percent of Total Investments 4.70%
C000013157 | Special Tax Revenue  
Holdings [Line Items]  
Percent of Total Investments 3.20%
C000013157 | Education  
Holdings [Line Items]  
Percent of Total Investments 8.70%
C000013157 | Housing  
Holdings [Line Items]  
Percent of Total Investments 5.70%
C000013157 | Hospital  
Holdings [Line Items]  
Percent of Total Investments 14.20%
C000013157 | Transportation  
Holdings [Line Items]  
Percent of Total Investments 16.10%
C000013157 | General Obligations  
Holdings [Line Items]  
Percent of Total Investments 14.30%
C000013157 | Water and Sewer  
Holdings [Line Items]  
Percent of Total Investments 11.80%
C000013157 | Senior Living/Life Care  
Holdings [Line Items]  
Percent of Total Investments 7.40%
C000013157 | Lease Rev./Cert. of Participation  
Holdings [Line Items]  
Percent of Total Investments 7.10%
C000013157 | Short-Term Investments  
Holdings [Line Items]  
Percent of Total Investments 3.10%
C000013157 | Bond Bank  
Holdings [Line Items]  
Percent of Total Investments 3.70%
C000013159 | Not Rated  
Holdings [Line Items]  
Percent of Total Investments 8.20%
C000013159 | BB  
Holdings [Line Items]  
Percent of Total Investments 3.00%
C000013159 | BBB  
Holdings [Line Items]  
Percent of Total Investments 6.70%
C000013159 | A  
Holdings [Line Items]  
Percent of Total Investments 5.20%
C000013159 | AA  
Holdings [Line Items]  
Percent of Total Investments 57.70%
C000013159 | AAA  
Holdings [Line Items]  
Percent of Total Investments 18.10%
C000013159 | B  
Holdings [Line Items]  
Percent of Total Investments 1.10%
C000013159 | Industry Other Line  
Holdings [Line Items]  
Percent of Total Investments 4.70%
C000013159 | Special Tax Revenue  
Holdings [Line Items]  
Percent of Total Investments 3.20%
C000013159 | Education  
Holdings [Line Items]  
Percent of Total Investments 8.70%
C000013159 | Housing  
Holdings [Line Items]  
Percent of Total Investments 5.70%
C000013159 | Hospital  
Holdings [Line Items]  
Percent of Total Investments 14.20%
C000013159 | Transportation  
Holdings [Line Items]  
Percent of Total Investments 16.10%
C000013159 | General Obligations  
Holdings [Line Items]  
Percent of Total Investments 14.30%
C000013159 | Water and Sewer  
Holdings [Line Items]  
Percent of Total Investments 11.80%
C000013159 | Senior Living/Life Care  
Holdings [Line Items]  
Percent of Total Investments 7.40%
C000013159 | Lease Rev./Cert. of Participation  
Holdings [Line Items]  
Percent of Total Investments 7.10%
C000013159 | Short-Term Investments  
Holdings [Line Items]  
Percent of Total Investments 3.10%
C000013159 | Bond Bank  
Holdings [Line Items]  
Percent of Total Investments 3.70%
C000063953 | Not Rated  
Holdings [Line Items]  
Percent of Total Investments 8.20%
C000063953 | BB  
Holdings [Line Items]  
Percent of Total Investments 3.00%
C000063953 | BBB  
Holdings [Line Items]  
Percent of Total Investments 6.70%
C000063953 | A  
Holdings [Line Items]  
Percent of Total Investments 5.20%
C000063953 | AA  
Holdings [Line Items]  
Percent of Total Investments 57.70%
C000063953 | AAA  
Holdings [Line Items]  
Percent of Total Investments 18.10%
C000063953 | B  
Holdings [Line Items]  
Percent of Total Investments 1.10%
C000063953 | Industry Other Line  
Holdings [Line Items]  
Percent of Total Investments 4.70%
C000063953 | Special Tax Revenue  
Holdings [Line Items]  
Percent of Total Investments 3.20%
C000063953 | Education  
Holdings [Line Items]  
Percent of Total Investments 8.70%
C000063953 | Housing  
Holdings [Line Items]  
Percent of Total Investments 5.70%
C000063953 | Hospital  
Holdings [Line Items]  
Percent of Total Investments 14.20%
C000063953 | Transportation  
Holdings [Line Items]  
Percent of Total Investments 16.10%
C000063953 | General Obligations  
Holdings [Line Items]  
Percent of Total Investments 14.30%
C000063953 | Water and Sewer  
Holdings [Line Items]  
Percent of Total Investments 11.80%
C000063953 | Senior Living/Life Care  
Holdings [Line Items]  
Percent of Total Investments 7.40%
C000063953 | Lease Rev./Cert. of Participation  
Holdings [Line Items]  
Percent of Total Investments 7.10%
C000063953 | Short-Term Investments  
Holdings [Line Items]  
Percent of Total Investments 3.10%
C000063953 | Bond Bank  
Holdings [Line Items]  
Percent of Total Investments 3.70%