Loans and Allowance for Credit Losses on Loans - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Allowance for Credit Losses on Loans
Loans, net	$ 2,651,594		$ 2,651,594		$ 2,510,559
Interest Income generated from Loans	32,635	$ 27,264	100,262	$ 81,321
Deferred loan fees	$ 8,463		$ 8,463		$ 319

Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant