Investments Investments (Realized GL info) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Debt Securities, Available-for-sale, Realized Gain (Loss) [Abstract]
Gross realized investment gains	$ 2	$ 6	$ 12	$ 28
Gross realized investment losses		(2)	(2)	(14)
Credit Losses		(15)	(13)	(15)
Total	$ 2	$ (11)	$ (3)	$ (1)

This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration