Investments - General, Narrative (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Investments [Abstract]
Investment securities in a continuous unrealized loss position for less then 12 months	$ 3,100,000,000		$ 3,100,000,000		$ 3,100,000,000
Investment securities unrealized loss	73,000,000		73,000,000
Estimated fair value for securities in continuous unrealized loss position for greater than 12 months	69,000,000		69,000,000		$ 0
Downward adjustments to the carrying value	0	$ 0	7,000,000	$ 0
Cumulative upward adjustments for observable price changes	41,000,000		41,000,000
Cumulative downward adjustments for price changes and impairment	$ 298,000,000		$ 298,000,000

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
-Section 50
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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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