v3.26.1
Shareholder Fees - Natixis Funds Trust I
Dec. 31, 2025
Mirova Global Megatrends Fund | Class A  
Prospectus [Line Items]  
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) 5.75%
Maximum Deferred Sales Charge (as a percentage of Offering Price) 0.00% [1]
Redemption Fee (as a percentage of Amount Redeemed) 0.00%
Mirova Global Megatrends Fund | Class C  
Prospectus [Line Items]  
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) 0.00%
Maximum Deferred Sales Charge (as a percentage of Offering Price) 1.00%
Redemption Fee (as a percentage of Amount Redeemed) 0.00%
Mirova Global Megatrends Fund | Class N  
Prospectus [Line Items]  
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) 0.00%
Maximum Deferred Sales Charge (as a percentage of Offering Price) 0.00%
Redemption Fee (as a percentage of Amount Redeemed) 0.00%
Mirova Global Megatrends Fund | Class Y  
Prospectus [Line Items]  
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) 0.00%
Maximum Deferred Sales Charge (as a percentage of Offering Price) 0.00%
Redemption Fee (as a percentage of Amount Redeemed) 0.00%
Vaughan Nelson Small Cap Fund | Class A  
Prospectus [Line Items]  
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) 5.75%
Maximum Deferred Sales Charge (as a percentage) 0.00% [2]
Redemption Fee (as a percentage of Amount Redeemed) 0.00%
Vaughan Nelson Small Cap Fund | Class C  
Prospectus [Line Items]  
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) 0.00%
Maximum Deferred Sales Charge (as a percentage) 1.00%
Redemption Fee (as a percentage of Amount Redeemed) 0.00%
Vaughan Nelson Small Cap Fund | Class N  
Prospectus [Line Items]  
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) 0.00%
Maximum Deferred Sales Charge (as a percentage) 0.00%
Redemption Fee (as a percentage of Amount Redeemed) 0.00%
Vaughan Nelson Small Cap Fund | Class Y  
Prospectus [Line Items]  
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) 0.00%
Maximum Deferred Sales Charge (as a percentage) 0.00%
Redemption Fee (as a percentage of Amount Redeemed) 0.00%
Natixis Oakmark International Fund | Class A  
Prospectus [Line Items]  
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) 5.75%
Maximum Deferred Sales Charge (as a percentage of Offering Price) 0.00% [3]
Redemption Fee (as a percentage of Amount Redeemed) 0.00%
Natixis Oakmark International Fund | Class C  
Prospectus [Line Items]  
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) 0.00%
Maximum Deferred Sales Charge (as a percentage of Offering Price) 1.00%
Redemption Fee (as a percentage of Amount Redeemed) 0.00%
Natixis Oakmark International Fund | Class N  
Prospectus [Line Items]  
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) 0.00%
Maximum Deferred Sales Charge (as a percentage of Offering Price) 0.00%
Redemption Fee (as a percentage of Amount Redeemed) 0.00%
Natixis Oakmark International Fund | Class Y  
Prospectus [Line Items]  
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) 0.00%
Maximum Deferred Sales Charge (as a percentage of Offering Price) 0.00%
Redemption Fee (as a percentage of Amount Redeemed) 0.00%
Natixis U.S. Equity Opportunities Fund | Class A  
Prospectus [Line Items]  
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) 5.75%
Maximum Deferred Sales Charge (as a percentage of Offering Price) 0.00%
Redemption Fee (as a percentage of Amount Redeemed) 0.00%
Natixis U.S. Equity Opportunities Fund | Class C  
Prospectus [Line Items]  
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) 0.00%
Maximum Deferred Sales Charge (as a percentage of Offering Price) 1.00% [4]
Redemption Fee (as a percentage of Amount Redeemed) 0.00%
Natixis U.S. Equity Opportunities Fund | Class N  
Prospectus [Line Items]  
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) 0.00%
Maximum Deferred Sales Charge (as a percentage of Offering Price) 0.00%
Redemption Fee (as a percentage of Amount Redeemed) 0.00%
Natixis U.S. Equity Opportunities Fund | Class Y  
Prospectus [Line Items]  
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) 0.00%
Maximum Deferred Sales Charge (as a percentage of Offering Price) 0.00%
Redemption Fee (as a percentage of Amount Redeemed) 0.00%
[1]
1 A 1.00% contingent deferred sales charge (“CDSC”) may apply to certain purchases of Class A shares of $1,000,000 or more that are redeemed within eighteen months of the date of purchase.
[2]
1 A 1.00% contingent deferred sales charge (“CDSC”) may apply to certain purchases of Class A shares of $1,000,000 or more that are redeemed within eighteen months of the date of purchase.
[3]
* A 1.00% contingent deferred sales charge (“CDSC”) may apply to certain purchases of Class A shares of $1,000,000 or more that are redeemed within eighteen months of the date of purchase.
[4]
1 A 1.00% contingent deferred sales charge (“CDSC”) may apply to certain purchases of Class A shares of $1,000,000 or more that are redeemed within eighteen months of the date of purchase.