Loans and Allowance for Credit Losses - Detail activity in the allowance for credit losses by portfolio segment (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 109,579	$ 73,658
Loans charged-off	(5,357)	(2,318)
Recoveries of loans previously charged-off	109	72
Net loans (charged-off) recoveries	(5,248)	(2,246)
Provision for credit losses- loans	(2,261)	14,310
Individually evaluated for impairment	12,505	11,833
Collectively evaluated for impairment	89,565	84,503
Ending Balance	102,070	96,336
Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Ending Balance		10,614
Commercial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	26,569	18,832
Loans charged-off	(4,150)	0
Recoveries of loans previously charged-off	96	69
Net loans (charged-off) recoveries	(4,054)	69
Provision for credit losses- loans	1,186	7,553
Individually evaluated for impairment	5,365	7,239
Collectively evaluated for impairment	18,336	20,107
Ending Balance	23,701	27,346
Commercial \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Ending Balance		892
Income producing - commercial real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	55,385	29,265
Loans charged-off	(1,000)	(550)
Recoveries of loans previously charged-off	0	0
Net loans (charged-off) recoveries	(1,000)	(550)
Provision for credit losses- loans	(2,875)	3,606
Individually evaluated for impairment	5,734	1,903
Collectively evaluated for impairment	45,776	41,648
Ending Balance	51,510	43,551
Income producing - commercial real estate \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Ending Balance		11,230
Owner occupied - commercial real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	14,000	5,838
Loans charged-off	0	0
Recoveries of loans previously charged-off	0	0
Net loans (charged-off) recoveries	0	0
Provision for credit losses- loans	315	(645)
Individually evaluated for impairment	1,076	375
Collectively evaluated for impairment	13,239	9,492
Ending Balance	14,315	9,867
Owner occupied - commercial real estate \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Ending Balance		4,674
Real estate mortgage - residential
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,020	1,557
Loans charged-off	0	0
Recoveries of loans previously charged-off	0	0
Net loans (charged-off) recoveries	0	0
Provision for credit losses- loans	(101)	113
Individually evaluated for impairment	330	657
Collectively evaluated for impairment	589	712
Ending Balance	919	1,369
Real estate mortgage - residential \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Ending Balance		(301)
Construction - commercial and residential
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	11,529	17,485
Loans charged-off	(206)	(1,768)
Recoveries of loans previously charged-off	0	0
Net loans (charged-off) recoveries	(206)	(1,768)
Provision for credit losses- loans	(640)	3,767
Individually evaluated for impairment	0	1,554
Collectively evaluated for impairment	10,683	11,787
Ending Balance	10,683	13,341
Construction - commercial and residential \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Ending Balance		(6,143)
Home equity
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,039	656
Loans charged-off	0	0
Recoveries of loans previously charged-off	0	0
Net loans (charged-off) recoveries	0	0
Provision for credit losses- loans	(132)	(83)
Individually evaluated for impairment	0	105
Collectively evaluated for impairment	907	713
Ending Balance	907	818
Home equity \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Ending Balance		245
Other consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	37	25
Loans charged-off	(1)	0
Recoveries of loans previously charged-off	13	3
Net loans (charged-off) recoveries	12	3
Provision for credit losses- loans	(14)	(1)
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	35	44
Ending Balance	$ 35	44
Other consumer \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Ending Balance		$ 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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