Investments, Available-for-sale Impairment Losses Recognized in Earnings (Details) - Fixed Maturity Securities Available-for-sale [Member] - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Available-For-Sale Impairment Losses [Abstract]
Impairment losses recognized in earnings	$ 11	$ 6	$ 103	$ 20
Corporate and Other Bonds [Member]
Available-For-Sale Impairment Losses [Abstract]
Impairment losses recognized in earnings	(1)	$ 6	90	12
Asset-Backed [Member]
Available-For-Sale Impairment Losses [Abstract]
Impairment losses recognized in earnings	$ 12		$ 13	$ 8

Amount of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in earnings.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 8A
-URI http://asc.fasb.org/extlink&oid=121553693&loc=SL6284422-111562

Name:	us-gaap_OtherThanTemporaryImpairmentLossDebtSecuritiesAvailableForSaleRecognizedInEarnings
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration