Noninterest Income - Gains and Losses on Investments (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Other Income and Expenses [Abstract]
Total net gains on non-marketable and other equity securities	$ 167,078	$ (15,110)
Gains on sales of available-for-sale securities, net	0	61,165
Gains on investment securities, net	$ 167,078	$ 46,055

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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