Income Taxes - Deferred Tax Assets (Liabilities) (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Deferred tax assets:
Accrued expenses	$ 3,681,000	$ 1,307,000
Net operating loss	5,681,000	6,614,000
Allowance for credit losses, net of bad debt charge-offs	64,628,000	85,700,000
Deferred compensation	3,338,000	3,489,000
State taxes	6,834,000	4,395,000
Loan net discounts	21,980,000	32,484,000
Stock-based compensation	4,030,000	4,618,000
Operating lease liabilities	20,708,000	24,463,000
Unrealized loss on available-for-sale securities	3,156,000	0
Federal and state credit carryovers	2,242,000	3,750,000
Other	0	1,782,000
Total deferred tax assets	136,278,000	168,602,000
Deferred tax liabilities:
Operating lease right-of-use assets	(18,272,000)	(21,756,000)
Deferred FDIC gain	(69,000)	(108,000)
Core deposit intangibles	(17,676,000)	(21,828,000)
Loan origination costs	(7,547,000)	(5,176,000)
Depreciation	(4,897,000)	(6,551,000)
Unrealized gain on available-for-sale securities	0	(24,127,000)
Other	(473,000)	0
Total deferred tax liabilities	(48,934,000)	(79,546,000)
Valuation allowance	0	0
Net deferred tax assets	$ 87,344,000	$ 89,056,000