Noninterest Income - Investment Banking Revenue (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Investment banking revenue:
Underwriting fees	$ 131,085	$ 42,584	$ 162,375	$ 78,356
Advisory fees	8,922	5,315	24,409	17,588
Private placements and other	1,496	795	1,586	2,545
Total investment banking revenue	$ 141,503	$ 48,694	$ 188,370	$ 98,489

Includes (1) underwriting revenue (the spread between the resale price received and the cost of the securities and related expenses) generated through the purchasing, distributing and reselling of new issues of securities (alternatively, could be a secondary offering of a large block of previously issued securities); and (2) fees earned for mergers, acquisitions, divestitures, restructurings, and other types of financial advisory services.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13(b),(d))
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

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Balance Type:	credit
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