Loans (Composition of Loan Portfolio) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	$ 6,662,133	$ 6,738,795
Allowance for credit losses	(204,809)	(116,539)
Total loans held for investment	6,457,324	6,622,256
Mortgage loans held for sale	41,654	19,591
Other loans held for sale	2,281	0
Total loans held for sale	43,935	19,591
Total loans	6,501,259	6,641,847
Commercial Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	2,402,010	2,218,351
Mortgage Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	2,283,375	2,493,365
Consumer Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	1,976,748	2,027,079
Acquired Non-PCD [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	4,890,114	4,726,493
Allowance for credit losses	(161,015)
Total loans held for investment	4,729,099
Mortgage loans held for sale	41,654
Other loans held for sale	2,281
Total loans held for sale	43,935
Total loans	4,773,034
Acquired Non-PCD [Member] | Commercial Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	2,118,850	1,862,827
Acquired Non-PCD [Member] | Mortgage Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	823,443	899,595
Acquired Non-PCD [Member] | Consumer Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	1,947,821	1,964,071
Acquired PCD [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	1,772,019
Allowance for credit losses	(43,794)
Total loans held for investment	1,728,225
Mortgage loans held for sale	0
Other loans held for sale	0
Total loans held for sale	0
Total loans	1,728,225
Acquired PCD [Member] | Commercial Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	283,160
Acquired PCD [Member] | Mortgage Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	1,459,932
Acquired PCD [Member] | Consumer Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	28,927
Commercial Secured By Real Estate [Member] | Commercial Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	1,050,513	1,129,446
Commercial Secured By Real Estate [Member] | Acquired Non-PCD [Member] | Commercial Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	807,284	866,706
Commercial Secured By Real Estate [Member] | Acquired PCD [Member] | Commercial Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	243,229
Other Commercial And Industrial [Member] | Commercial Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	687,375	816,310
Other Commercial And Industrial [Member] | Acquired Non-PCD [Member] | Commercial Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	647,444	723,526
Other Commercial And Industrial [Member] | Acquired PCD [Member] | Commercial Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	39,931
Commercial Paycheck Protection Program [Member] | Commercial Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	289,218	0
Commercial Paycheck Protection Program [Member] | Acquired Non-PCD [Member] | Commercial Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	289,218
Commercial Paycheck Protection Program [Member] | Acquired PCD [Member] | Commercial Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	0
US Loan Program [Member] | Commercial Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	374,904	272,595
US Loan Program [Member] | Acquired Non-PCD [Member] | Commercial Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	374,904	272,595
US Loan Program [Member] | Acquired PCD [Member] | Commercial Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	0
Personal Loan [Member] | Consumer Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	314,300	375,505
Personal Loan [Member] | Acquired Non-PCD [Member] | Consumer Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	313,257	367,157
Personal Loan [Member] | Acquired PCD [Member] | Consumer Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	1,043
Credit Lines [Member] | Consumer Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	44,156	53,113
Credit Lines [Member] | Acquired Non-PCD [Member] | Consumer Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	43,805	52,614
Credit Lines [Member] | Acquired PCD [Member] | Consumer Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	351
Credit Cards [Member] | Consumer Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	56,185	75,272
Credit Cards [Member] | Acquired Non-PCD [Member] | Consumer Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	56,185	75,202
Credit Cards [Member] | Acquired PCD [Member] | Consumer Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	0
Overdraft [Member] | Consumer Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	305	216
Overdraft [Member] | Acquired Non-PCD [Member] | Consumer Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	305
Overdraft [Member] | Acquired PCD [Member] | Consumer Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	0
Auto Loan [Member] | Consumer Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	1,561,802	1,522,973
Auto Loan [Member] | Acquired Non-PCD [Member] | Consumer Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	1,534,269	1,468,882
Auto Loan [Member] | Acquired PCD [Member] | Consumer Portfolio Segment [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount	$ 27,533
Originated Loan [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount		3,907,350
Originated Loan [Member] | Auto Loan [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount		1,277,867
Originated Loan [Member] | Mortgage Loan [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount		577,416
Originated Loan [Member] | Commercial Loan [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount		1,669,635
Originated Loan [Member] | Consumer Loan [Member]
Loans And Leases Receivable Net Reported Amount
Loans and Leases Receivable, Gross, Carrying Amount		$ 382,432