Allowance For Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2021	Jun. 30, 2021	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery [Abstract]
PPP loans originated [Line Items]			$ 131,500	$ 331,600
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans collectively evaluated for impairment			6,820,448	7,058,225
Loan balance			6,908,417	7,177,785
Financing Receivable, Allowance for Credit Loss		$ 83,577	88,129	85,675	$ 87,038	$ 73,476	$ 56,679
Off-Balance Sheet, Credit Loss, Liability			4,642	116
Deferred Tax Liabilities, Net				2,892
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest			1,067,912	1,040,256
Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss				6,090
Off-Balance Sheet, Credit Loss, Liability				3,866
Deferred Tax Liabilities, Net				(2,115)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest				(7,956)
7000 Hotels, Rooming Houses, Camps and Other Lodging Places
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans collectively evaluated for impairment			123,249
Additional Reserve Pandemic Risk			1,854
Loan balance			193,800
7000 Hotels, Rooming Houses, Camps and Other Lodging Places | Financial Asset Originated
Financing Receivable, Allowance for Credit Loss [Line Items]
Additional Reserve Pandemic Risk			1,900
722110 Full-Service Restaurants
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans collectively evaluated for impairment			33,373
Additional Reserve Pandemic Risk			754
5331 Retail, Variety Stores
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans collectively evaluated for impairment			177,635
Additional Reserve Pandemic Risk			1,961
Hotels, Restaurants, Strip Shopping Total
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans collectively evaluated for impairment			334,257
Additional Reserve Pandemic Risk	$ 4,500	$ 3,400	$ 4,569	$ 3,800