Noninterest Income - Gains and Losses on Investments (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Other Income and Expenses [Abstract]
Total net gains on non-marketable and other equity securities	$ (15,110)	$ 32,658
Gains (losses) on sales of available-for-sale securities, net	61,165	(3,630)
Gains on investment securities, net	$ 46,055	$ 29,028

Amount of realized and unrealized gain (loss) on investment.

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