Equity - Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2022	Jun. 30, 2022	Sep. 30, 2022	Dec. 31, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ (7,321)	$ 0
Other comprehensive income (loss) before reclassifications	1,562	(2,914)
Less: Reclassification adjustments for gains (losses) realized	56	(45)
Less: Income tax expense (benefit)	290	(615)	$ (615)	$ (1,493)	$ (2,220)	$ (1,933)
Less: Other comprehensive income (loss) attributable to noncontrolling interests	(43)	(64)
Ending balance	(6,148)	(2,318)	(2,318)			(7,321)
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Noncontrolling Interest [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(12,565)	0
Less: Other comprehensive income (loss) attributable to noncontrolling interests	(220)	676
Ending balance	(10,879)	(4,747)	(4,747)			(12,565)
AOCI, Gain (Loss), Debt Securities, Available-for-sale, with Allowance for Credit Loss, Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(334)	0
Ending balance	(467)	(65)	(65)			(334)
DAC, DSI, VOBA, future policy benefits and dividends payable to policyholders adjustments on AFS securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Ending balance	109	(79)	(79)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	47	0
Ending balance						47
AOCI, Accumulated Gain (Loss), Debt Securities, with credit allowance, portion attributable to NCI [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Less: Other comprehensive income (loss) attributable to noncontrolling interests	0	9
Accumulated Foreign Currency Adjustment and Other Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(10)	0
Ending balance	(1)	5	5			(10)
AOCI, Gain (Loss), Debt Securities, Available-for-sale, with Allowance for Credit Loss, Including Noncontrolling Interest [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications	2,187	(6,645)
Less: Reclassification adjustments for gains (losses) realized	(31)	(38)
Less: Income tax expense (benefit)	312	(1,184)
AOCI, Gain (Loss), Debt Securities, Available-for-sale, with Allowance for Credit Loss, Including Noncontrolling Interest [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications	(119)	(97)
Less: Reclassification adjustments for gains (losses) realized	0	(7)
Less: Income tax expense (benefit)	14	(16)
Accumulated Net Gain (Loss) from Cash Flow Hedges Including Portion Attributable to Noncontrolling Interest [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications	191	(129)
Less: Reclassification adjustments for gains (losses) realized	87	0
Less: Income tax expense (benefit)	15	(26)
Accumulated Foreign Currency Adjustment and Other Including Portion Attributable to Noncontrolling Interest [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications	16	(2)
Less: Reclassification adjustments for gains (losses) realized	0	0
Less: Income tax expense (benefit)	4	(1)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Noncontrolling Interest [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Less: Other comprehensive income (loss) attributable to noncontrolling interests	(27)	24
Accumulated Foreign Currency Adjustment and Other Attributable to Noncontrolling Interest [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Less: Other comprehensive income (loss) attributable to noncontrolling interests	(3)	6
Remeasurement gains (losses) on future policy benefits related to discount rate
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	5,256	0
Other comprehensive income (loss) before reclassifications	(802)	3,562
Less: Reclassification adjustments for gains (losses) realized	0	0
Less: Income tax expense (benefit)	(73)	529
Less: Other comprehensive income (loss) attributable to noncontrolling interests	208	(774)
Ending balance	4,735	2,259	2,259			5,256
Remeasurement gains (losses) on market risk benefits related to credit risk
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	285	0
Other comprehensive income (loss) before reclassifications	89	397
Less: Reclassification adjustments for gains (losses) realized	0	0
Less: Income tax expense (benefit)	18	83
Less: Other comprehensive income (loss) attributable to noncontrolling interests	(1)	(5)
Ending balance	$ 355	$ 309	$ 309			$ 285