Segment Information - Schedule of Assets for Segments and Corporate and Other (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Segment Reporting Information [Line Items]
Assets	$ 86,773	$ 88,083
Enact
Segment Reporting Information [Line Items]
Assets	6,967	6,895
Closed Block
Segment Reporting Information [Line Items]
Assets	$ 78,472	$ 79,615

Amount of asset recognized for present right to economic benefit.

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+ Details