Shareholders' Equity - Progression of the components of accumulated other comprehensive income (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Accumulated Other Comprehensive Income [Roll Forward]
AOCI beginning balance			$ (319)
Other comprehensive income (loss), pretax	$ 249	$ (73)	236	$ (33)
Other comprehensive income (loss), tax	(54)	14	(53)	6
Other comprehensive income (loss), net of tax	195	(59)	183	(27)
AOCI ending balance	(136)		(136)
Net unrealized gains (losses) on securities:
Unrealized holding gains (losses) on securities arising during the period, pretax	226	(81)	216	(69)
Unrealized holding gains (losses) on securities arising during the period, tax	(48)	17	(46)	14
Unrealized holding gains (losses) on securities arising during the period, after tax	178	(64)	170	(55)
Reclassification adjustment for realized (gains) losses included in net earnings, pretax	15	9	21	40
Reclassification adjustment for realized (gains) losses included in net earnings, tax	(3)	(2)	(4)	(9)
Reclassification adjustment for realized (gains) losses included in net earnings, after tax	12	7	17	31
Total net unrealized gains (losses) on securities, pretax	241	(72)	237	(29)
Total net unrealized gains (losses) on securities, tax	(51)	15	(50)	5
Total net unrealized gains (losses) on securities	190	(57)	187	(24)
Net unrealized gains (losses) on cash flow hedges:
Unrealized holding gains (losses) on cash flow hedges arising during the period, pretax	11	(9)	(7)	(25)
Unrealized holding gains (losses) on cash flow hedges arising during the period, tax	(3)	2	1	5
Unrealized holding gains (losses) on cash flow hedges arising during the period, after tax	8	(7)	(6)	(20)
Reclassification adjustment for investment income included in net earnings, pretax	6	8	20	19
Reclassification adjustment for investment income included in net earnings, tax	(1)	(2)	(4)	(4)
Reclassification adjustment for investment income included in net earnings from discontinued operations, after tax	5	6	16	15
Total net unrealized gains (losses) on cash flow hedges, pretax	17	(1)	13	(6)
Total net unrealized gains (losses) on cash flow hedges, tax	(4)	0	(3)	1
Total net unrealized gains (losses) on cash flow hedges	13	(1)	10	(5)
Foreign currency translation adjustments, pretax	(9)	0	(14)	2
Foreign currency translation adjustments, tax	1	(1)	0	0
Foreign currency translation adjustments, after tax	(8)	(1)	(14)	2
Total pension and OPRP adjustments, pretax	0	0	0	0
Total pension and OPRP adjustments, tax	0	0	0	0
Total pension and OPRP adjustments, after Tax	0	0	0	0
AOCI attributable to parent
Accumulated Other Comprehensive Income [Roll Forward]
AOCI beginning balance	(331)	(511)	(319)	(543)
AOCI ending balance	(136)	(570)	(136)	(570)
Accumulated net investment gain (loss) attributable to parent
Accumulated Other Comprehensive Income [Roll Forward]
AOCI beginning balance	(290)	(464)	(287)	(497)
AOCI ending balance	(100)	(521)	(100)	(521)
Accumulated gain (loss), net, cash flow hedge, parent
Accumulated Other Comprehensive Income [Roll Forward]
AOCI beginning balance	(20)	(33)	(17)	(29)
AOCI ending balance	(7)	(34)	(7)	(34)
Accumulated foreign currency adjustment attributable to parent
Accumulated Other Comprehensive Income [Roll Forward]
AOCI beginning balance	(23)	(17)	(17)	(20)
AOCI ending balance	(31)	(18)	(31)	(18)
Accumulated defined benefit plans adjustment attributable to parent
Accumulated Other Comprehensive Income [Roll Forward]
AOCI beginning balance	2	3	2	3
AOCI ending balance	$ 2	$ 3	$ 2	$ 3