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Segment Information - Segment Information (Details) $ in Millions	3 Months Ended
	Mar. 31, 2022 USD ($) segment	Mar. 31, 2021 USD ($)
Segment Reporting [Abstract]
Number of reportable segments | segment	2
Segment Reporting Information [Line Items]
Segment equity in earnings (losses) of investees	$ (11)	$ 9
Operating Segments
Segment Reporting Information [Line Items]
Segment equity in earnings (losses) of investees	(1)	19
Segment adjusted operating income (loss)	133	72
Insurance | Operating Segments
Segment Reporting Information [Line Items]
Revenue, including adjustments	276	177
Segment revenues	278	179
Segment expenses	122	106
Segment equity in earnings (losses) of investees	(1)	19
Less: Segment provision (benefit) for income taxes	22	13
Segment adjusted operating income (loss)	133	79
Insurance | Intersegment Eliminations
Segment Reporting Information [Line Items]
Revenue, including adjustments	2	2
Asset Management | Operating Segments
Segment Reporting Information [Line Items]
Revenue, including adjustments	30	18
Segment revenues	39	20
Segment expenses	39	29
Segment equity in earnings (losses) of investees	0	0
Less: Segment provision (benefit) for income taxes	0	(2)
Segment adjusted operating income (loss)	0	(7)
Asset Management | Intersegment Eliminations
Segment Reporting Information [Line Items]
Revenue, including adjustments	$ 9	$ 2

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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