Investments (Fair Values by Contractual Maturity) (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract]
Maturing in one year or less	$ 10,681	$ 5,629
Maturing after one year through three years	53	2,304
Maturing after three years through five years	0	119
Residential-mortgage-backed securities	0	182
Total interest-bearing securities	$ 10,734	$ 8,234

Available-For Sale Securities, Debt Maturities, After One Through Three Years, Fair Value

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- Definition

Available-For-Sale Securities, Debt Maturities, After Three Through Five Years, Fair Value

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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), maturing in next fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), without single maturity date and not allocated over maturity grouping.

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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).

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