Investment Securities (Details 1) $ in Millions	Mar. 31, 2021 USD ($) security	Dec. 31, 2020 security
Debt Securities, Available-for-sale [Line Items]
Number of securities with gross unrealized losses \| security	10	0
Estimated Fair Value
Less than 12 months	$ 35
12 months or more	0
Gross Unrealized Losses
Less than 12 months	(1)
12 months or more	0
State and municipal obligations
Estimated Fair Value
Less than 12 months	35
12 months or more	0
Gross Unrealized Losses
Less than 12 months	(1)
12 months or more	$ 0

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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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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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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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