Average Annual Total Returns |
12 Months Ended | 60 Months Ended | 120 Months Ended |
|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2025 |
Dec. 31, 2025 |
|
| Bloomberg U.S. Aggregate Bond Index (reflects no deduction for fees, expenses or taxes)[Member] | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 7.30% | (0.36%) | 2.01% |
| Elfun Income Fund | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 7.34% | (0.54%) | 2.08% |
| Elfun Income Fund | After Taxes on Distributions | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 5.66% | (2.08%) | 0.66% |
| Elfun Income Fund | After Taxes on Distributions and Sales | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 4.32% | (1.05%) | 0.99% |