Investment Securities (Details 1) $ in Millions	Dec. 31, 2021 USD ($) security	Dec. 31, 2020 security
Debt Securities, Available-for-sale [Line Items]
Number of available-for-sale debt securities with gross unrealized losses \| security	5	0
Available-for-sale investment securities with gross unrealized losses and length of time
Estimated Fair Value, Less than 12 months	$ 477
Estimated Fair Value, 12 months or more	0
Available-for-sale investment securities with gross unrealized losses
Gross Unrealized Losses, Less than 12 months	(1)
Gross Unrealized Losses, 12 months or more	0
U.S. Government treasury obligations
Available-for-sale investment securities with gross unrealized losses and length of time
Estimated Fair Value, Less than 12 months	477
Estimated Fair Value, 12 months or more	0
Available-for-sale investment securities with gross unrealized losses
Gross Unrealized Losses, Less than 12 months	(1)
Gross Unrealized Losses, 12 months or more	$ 0

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Debt Securities, Available-for-sale, Unrealized Loss Position1

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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 more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

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Amount of accumulated unrealized loss on 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 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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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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Amount of accumulated unrealized loss on 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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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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