Noninterest Income - Gains on Investment Securities, Net (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Gains on non-marketable and other equity securities, net	$ 359,587	$ 138,575	$ 88,834
Gains (losses) on sales of available-for-sale debt securities, net	61,165	(3,905)	(740)
Gains on investment securities, net	$ 420,752	$ 134,670	$ 88,094

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Publisher FASB
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