Acquisitions - Acquisition of SOP Holdings, LLC (Details) - USD ($) $ in Thousands		3 Months Ended
Jan. 03, 2020	Mar. 31, 2020
Business Acquisition
Transaction costs		$ 851
Sandler O'Neill
Business Acquisition
Purchase price	$ 485,000
Amount of tangible book value the Company was entitled to receive	100,000
Acquisition-related compensation arrangements	113,900
Goodwill recorded	94,200	94,159
Intangible assets	157,600
Transaction costs		$ 900
Sandler O'Neill \| Trade name
Business Acquisition
Intangible assets	85,400
Sandler O'Neill \| Customer relationships
Business Acquisition
Intangible assets	$ 72,200
Sandler O'Neill \| Restricted Stock
Business Acquisition
Restricted shares granted as equity consideration (in shares)	1,568,670
Value of restricted shares granted as equity consideration	$ 124,900
Deal consideration vesting period	3 years
Requisite service period	3 years
Acquisition-related compensation arrangements	$ 96,900
Sandler O'Neill \| Restricted Stock \| 2020 Inducement Plan \| Weighted Average
Business Acquisition
Award vesting period in years		3 years 8 months 12 days
Sandler O'Neill \| Restricted Stock \| 2020 Inducement Plan \| 18 Month Vesting Period
Business Acquisition
Award vesting period in years		18 months
Sandler O'Neill \| Restricted Stock \| 2020 Inducement Plan \| Three Year Vesting Period
Business Acquisition
Award vesting period in years		3 years
Sandler O'Neill \| Restricted Stock \| 2020 Inducement Plan \| Five Year Vesting Period
Business Acquisition
Award vesting period in years		5 years
Sandler O'Neill \| Restricted cash
Business Acquisition
Acquisition-related compensation arrangements	$ 17,000

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