Investment Securities (Details 2) $ in Millions	Dec. 31, 2020 security	Dec. 31, 2019 USD ($) security
Available-for-sale investment securities with gross unrealized losses
Number of Securities, Less than 12 months \| security		2
Number of Securities, 12 months or more \| security		3
Number of Securities, Total \| security	0	5
Available-for-sale investment securities with gross unrealized losses and length of time
Estimated Fair Value, Less than 12 months		$ 18
Estimated Fair Value, 12 months or more		324
Estimated Fair Value, Total		342
Available-for-sale investment securities with gross unrealized losses
Gross Unrealized Losses, Less than 12 months		(1)
Gross Unrealized Losses, 12 months or more		(1)
Gross Unrealized Losses, Total		$ (2)
Ratio of fair value to amortized cost between 90%-100% [Member]
Available-for-sale investment securities with gross unrealized losses
Number of Securities, Less than 12 months \| security		2
Number of Securities, 12 months or more \| security		3
Number of Securities, Total \| security		5
Available-for-sale investment securities with gross unrealized losses and length of time
Estimated Fair Value, Less than 12 months		$ 18
Estimated Fair Value, 12 months or more		324
Estimated Fair Value, Total		342
Available-for-sale investment securities with gross unrealized losses
Gross Unrealized Losses, Less than 12 months		(1)
Gross Unrealized Losses, 12 months or more		(1)
Gross Unrealized Losses, Total		$ (2)

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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.

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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 continuous unrealized loss position for 12 months or longer, without an allowance for credit loss. Includes beneficial interest in securitized financial asset.

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