Investment Securities and Certificates of Deposit - Scheduled Maturities of Available-for-Sale Debt Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract]
Due within one year, amortized cost	$ 4,951	$ 108,662
Due after one year through five years, amortized cost	7,100	5,542
Due after ten years, amortized cost	1,009	0
Debt Securities, Available-for-sale, Amortized Cost	13,060	114,204
Due within one year, fair value	4,981	109,217
Due after one year through five years, fair value	7,130	5,567
Due after ten years, fair value	1,008	0
Total, fair value	$ 13,119	$ 114,784

Amortized cost 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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