Consolidated Statements of Operations and Comprehensive Income (Parentheticals) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Income Statement [Abstract]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Tax	$ (22)	$ 4
Total net realized gains (losses) reclassified from AOCI	$ (136)	$ 24

Amount before tax of reclassification adjustments of other comprehensive income (loss).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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