Loans and Allowance for Credit Losses - Detail activity in the allowance for credit losses by portfolio segment (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 92,560	$ 108,796	$ 109,579	$ 73,658
Loans charged-off	(2,000)	(5,228)	(13,114)	(14,691)
Recoveries of loans previously charged-off	672	58	939	136
Net loans (charged-off) recoveries	(1,328)	(5,170)	(12,175)	(14,555)
Provision for credit losses- loans	8,326	(6,589)	14,498	(40,498)
Individually evaluated for impairment	9,303	17,617	9,303	17,617
Collectively evaluated for impairment	73,603	92,598	73,603	92,598
Ending Balance	82,906	110,215	82,906	110,215
Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Ending Balance		10,614		10,614
Commercial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	21,348	28,078	26,569	18,832
Loans charged-off	(1,999)	(187)	(7,691)	(7,332)
Recoveries of loans previously charged-off	81	45	326	116
Net loans (charged-off) recoveries	(1,918)	(142)	(7,365)	(7,216)
Provision for credit losses- loans	2,503	712	2,277	(14,716)
Individually evaluated for impairment	3,198	9,593	3,198	9,593
Collectively evaluated for impairment	13,729	17,631	13,729	17,631
Ending Balance	16,927	27,224	16,927	27,224
Commercial \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Ending Balance		892		892
Income producing - commercial real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	45,970	51,863	55,385	29,265
Loans charged-off	0	(3,750)	(5,216)	(4,300)
Recoveries of loans previously charged-off	97	0	97	0
Net loans (charged-off) recoveries	97	(3,750)	(5,119)	(4,300)
Provision for credit losses- loans	4,636	(7,327)	8,835	(19,245)
Individually evaluated for impairment	5,439	5,999	5,439	5,999
Collectively evaluated for impairment	35,992	49,441	35,992	49,441
Ending Balance	41,431	55,440	41,431	55,440
Income producing - commercial real estate \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Ending Balance		11,230		11,230
Owner occupied - commercial real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	12,995	12,341	14,000	5,838
Loans charged-off	0	(20)	0	(20)
Recoveries of loans previously charged-off	0	0	0	0
Net loans (charged-off) recoveries	0	(20)	0	(20)
Provision for credit losses- loans	1,050	(769)	2,055	(2,598)
Individually evaluated for impairment	0	670	0	670
Collectively evaluated for impairment	11,945	12,420	11,945	12,420
Ending Balance	11,945	13,090	11,945	13,090
Owner occupied - commercial real estate \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Ending Balance		4,674		4,674
Real estate mortgage - residential
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	882	1,550	1,020	1,557
Loans charged-off	0	0	0	0
Recoveries of loans previously charged-off	0	0	0	0
Net loans (charged-off) recoveries	0	0	0	0
Provision for credit losses- loans	(172)	(321)	(34)	(615)
Individually evaluated for impairment	501	1,148	501	1,148
Collectively evaluated for impairment	553	723	553	723
Ending Balance	1,054	1,871	1,054	1,871
Real estate mortgage - residential \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Ending Balance		(301)		(301)
Construction - commercial and residential
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	10,427	13,808	11,529	17,485
Loans charged-off	0	(1,179)	(206)	(2,947)
Recoveries of loans previously charged-off	493	0	499	0
Net loans (charged-off) recoveries	493	(1,179)	293	(2,947)
Provision for credit losses- loans	179	1,088	1,081	(3,146)
Individually evaluated for impairment	0	204	0	204
Collectively evaluated for impairment	10,741	11,337	10,741	11,337
Ending Balance	10,741	11,541	10,741	11,541
Construction - commercial and residential \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Ending Balance		(6,143)		(6,143)
Home equity
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	897	1,112	1,039	656
Loans charged-off	0	(92)	0	(92)
Recoveries of loans previously charged-off	0	0		0
Net loans (charged-off) recoveries	0	(92)	0	(92)
Provision for credit losses- loans	129	13	271	(198)
Individually evaluated for impairment	165	0	165	0
Collectively evaluated for impairment	603	1,007	603	1,007
Ending Balance	768	1,007	768	1,007
Home equity \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Ending Balance		245		245
Other consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	41	44	37	25
Loans charged-off	(1)	0	(1)	0
Recoveries of loans previously charged-off	1	13	17	20
Net loans (charged-off) recoveries	0	13	16	20
Provision for credit losses- loans	1	15	13	20
Individually evaluated for impairment	0	3	0	3
Collectively evaluated for impairment	40	39	40	39
Ending Balance	$ 40	42	$ 40	42
Other consumer \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Ending Balance		$ 17		$ 17

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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Amount, after recoveries, of loans and leases that have been written-off.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of expense related to estimated loss from loan and lease transactions.

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