Investments - Schedule of Unrealized Investment Gains and Losses Reflected as a Separate Component of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions |
Jun. 30, 2026 |
Mar. 31, 2026 |
Dec. 31, 2025 |
Jun. 30, 2025 |
Mar. 31, 2025 |
Dec. 31, 2024 |
|---|---|---|---|---|---|---|
| Investments, Debt and Equity Securities [Abstract] | ||||||
| Net unrealized gains (losses) on fixed maturity securities without an allowance for credit losses | $ (2,939) | $ (2,356) | ||||
| Net unrealized gains (losses) on fixed maturity securities with an allowance for credit losses | (3) | (9) | ||||
| Adjustments to policyholder contract balances | 73 | 66 | ||||
| Income taxes, net | 428 | 307 | ||||
| Net unrealized investment gains (losses) | (2,441) | (1,992) | ||||
| Less: net unrealized investment gains (losses) attributable to noncontrolling interests | (15) | (5) | ||||
| Net unrealized investment gains (losses) attributable to Genworth Financial, Inc. | $ (2,426) | $ (2,526) | $ (1,987) | $ (2,536) | $ (2,660) | $ (3,156) |