Deferred Acquisition Costs (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2026	Dec. 31, 2025
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Beginning balance	$ 1,586
Ending balance	1,540	$ 1,586
Total deferred acquisition costs	1,540	1,586
Enact segment
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Beginning balance	22
Ending balance	22	22
Total deferred acquisition costs	22	22
Long-duration insurance contracts
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Beginning balance	1,564	1,755
Costs deferred	0	0
Amortization	(46)	(191)
Ending balance	1,518	1,564
Total deferred acquisition costs	1,518	1,564
Long- term care insurance
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Beginning balance	769	823
Costs deferred	0	0
Amortization	(13)	(54)
Ending balance	756	769
Total deferred acquisition costs	756	769
Life insurance
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Beginning balance	694	812
Costs deferred	0	0
Amortization	(28)	(118)
Ending balance	666	694
Total deferred acquisition costs	666	694
Fixed annuities
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Beginning balance	30	37
Costs deferred	0	0
Amortization	(2)	(7)
Ending balance	28	30
Total deferred acquisition costs	28	30
Variable annuities
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Beginning balance	71	83
Costs deferred	0	0
Amortization	(3)	(12)
Ending balance	68	71
Total deferred acquisition costs	$ 68	$ 71