Loans and Allowance for Credit Losses - Detail activity in the allowance for credit losses by portfolio segment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 102,070	$ 96,336	$ 109,579	$ 73,658
Loans charged-off	(5,757)	(7,145)	(11,114)	(9,463)
Recoveries of loans previously charged-off	158	6	267	78
Net loans (charged-off) recoveries	(5,599)	(7,139)	(10,847)	(9,385)
Provision for credit losses- loans	(3,911)	19,599	(6,172)	33,909
Individually evaluated for impairment	10,802	16,701	10,802	16,701
Collectively evaluated for impairment	81,758	92,095	81,758	92,095
Ending Balance	92,560	108,796	92,560	108,796
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	23,701	27,346	26,569	18,832
Loans charged-off	(1,541)	(7,145)	(5,691)	(7,145)
Recoveries of loans previously charged-off	150	5	246	74
Net loans (charged-off) recoveries	(1,391)	(7,140)	(5,445)	(7,071)
Provision for credit losses- loans	(962)	7,872	224	15,425
Individually evaluated for impairment	4,941	8,797	4,941	8,797
Collectively evaluated for impairment	16,407	19,281	16,407	19,281
Ending Balance	21,348	28,078	21,348	28,078
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	51,510	43,551	55,385	29,265
Loans charged-off	(4,216)	0	(5,216)	(550)
Recoveries of loans previously charged-off	0	0	0	0
Net loans (charged-off) recoveries	(4,216)	0	(5,216)	(550)
Provision for credit losses- loans	(1,324)	8,312	(4,199)	11,918
Individually evaluated for impairment	4,923	5,260	4,923	5,260
Collectively evaluated for impairment	41,047	46,603	41,047	46,603
Ending Balance	45,970	51,863	45,970	51,863
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	14,315	9,867	14,000	5,838
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	(1,320)	2,474	(1,005)	1,829
Individually evaluated for impairment	436	405	436	405
Collectively evaluated for impairment	12,559	11,936	12,559	11,936
Ending Balance	12,995	12,341	12,995	12,341
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	919	1,369	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	(37)	181	(138)	294
Individually evaluated for impairment	330	746	330	746
Collectively evaluated for impairment	552	804	552	804
Ending Balance	882	1,550	882	1,550
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	10,683	13,341	11,529	17,485
Loans charged-off	0		(206)	(1,768)
Recoveries of loans previously charged-off	6		6	0
Net loans (charged-off) recoveries	6	0	(200)	(1,768)
Provision for credit losses- loans	(262)	467	(902)	4,234
Individually evaluated for impairment	0	1,383	0	1,383
Collectively evaluated for impairment	10,427	12,425	10,427	12,425
Ending Balance	10,427	13,808	10,427	13,808
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	907	818	1,039	656
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	(10)	294	(142)	211
Individually evaluated for impairment	172	107	172	107
Collectively evaluated for impairment	725	1,005	725	1,005
Ending Balance	897	1,112	897	1,112
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	35	44	37	25
Loans charged-off	0	0	(1)	0
Recoveries of loans previously charged-off	2	1	15	4
Net loans (charged-off) recoveries	2	1	14	4
Provision for credit losses- loans	4	(1)	(10)	(2)
Individually evaluated for impairment	0	3	0	3
Collectively evaluated for impairment	41	41	41	41
Ending Balance	$ 41	44	$ 41	44
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 valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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

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