Noninterest Income - Gains and Losses on Derivatives (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Other Income and Expenses [Abstract]
Gains on exercises, net	$ 9,435	$ 40,226	$ 32,730	$ 49,180
Terminations	(439)	(1,045)	(872)	(1,884)
Changes in fair value, net	17,510	9,166	8,043	22,356
Gains on equity warrant assets, net	$ 26,506	$ 48,347	$ 39,901	$ 69,652

Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5618551-113959

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration