Loans and Leases and Allowance for Credit Losses - Balance and activity in the ACL by portfolio segment and recorded investment in loans by portfolio segment (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	$ 62,089	$ 61,203
Allowance for credit losses - loans, Charge-Offs	(10,805)	(4,360)
Allowance for credit losses - loans, Recoveries	2,691	1,230
Allowance for credit losses - loans, (Release) Provision	21,050	3,569
Allowance for credit losses - loans, Ending Balance	81,905	61,642
Allowance for unfunded commitments, Beginning Balance	3,458	3,410
Allowance for unfunded commitments, (Release) Provision	1,141	(269)
Allowance for unfunded commitments, Ending Balance	6,470	3,141
Total allowance for credit losses, Beginning Balance	65,547	64,613
Total allowance for credit losses, Charge-Offs	(10,805)	(4,360)
Total allowance for credit losses, Recoveries	2,691	1,230
Total allowance for credit losses, (Release) Provision	22,191	3,300
Total allowance for credit losses, Ending Balance	88,375	64,783
Adoption of CECL
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	6,880
Allowance for unfunded commitments, Beginning Balance	1,871
Total allowance for credit losses, Beginning Balance	8,751
Adjusted Balance
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	68,969
Allowance for unfunded commitments, Beginning Balance	5,329
Total allowance for credit losses, Beginning Balance	74,298
Loans receivable \| Indirect auto
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	0	999
Allowance for credit losses - loans, Charge-Offs	0	(197)
Allowance for credit losses - loans, Recoveries	0	38
Allowance for credit losses - loans, (Release) Provision	0	32
Allowance for credit losses - loans, Ending Balance	0	872
Loans receivable \| Indirect auto \| Adoption of CECL
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	0
Loans receivable \| Indirect auto \| Adjusted Balance
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	0
Loans receivable \| Commercial \| Owner occupied commercial real estate
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	11,404	12,207
Allowance for credit losses - loans, Charge-Offs	(6)	(5)
Allowance for credit losses - loans, Recoveries	1,034	69
Allowance for credit losses - loans, (Release) Provision	184	(397)
Allowance for credit losses - loans, Ending Balance	11,000	11,874
Loans receivable \| Commercial \| Owner occupied commercial real estate \| Adoption of CECL
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	(1,616)
Loans receivable \| Commercial \| Owner occupied commercial real estate \| Adjusted Balance
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	9,788
Loans receivable \| Commercial \| Income producing commercial real estate
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	12,306	11,073
Allowance for credit losses - loans, Charge-Offs	(411)	(197)
Allowance for credit losses - loans, Recoveries	141	20
Allowance for credit losses - loans, (Release) Provision	4,578	230
Allowance for credit losses - loans, Ending Balance	16,584	11,126
Loans receivable \| Commercial \| Income producing commercial real estate \| Adoption of CECL
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	(30)
Loans receivable \| Commercial \| Income producing commercial real estate \| Adjusted Balance
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	12,276
Loans receivable \| Commercial \| Commercial & industrial
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	5,266	4,802
Allowance for credit losses - loans, Charge-Offs	(7,561)	(1,519)
Allowance for credit losses - loans, Recoveries	376	163
Allowance for credit losses - loans, (Release) Provision	8,738	1,449
Allowance for credit losses - loans, Ending Balance	10,831	4,895
Loans receivable \| Commercial \| Commercial & industrial \| Adoption of CECL
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	4,012
Loans receivable \| Commercial \| Commercial & industrial \| Adjusted Balance
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	9,278
Loans receivable \| Commercial \| Construction
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	9,668	10,337
Allowance for credit losses - loans, Charge-Offs	0	(69)
Allowance for credit losses - loans, Recoveries	141	394
Allowance for credit losses - loans, (Release) Provision	2,330	(387)
Allowance for credit losses - loans, Ending Balance	9,556	10,275
Loans receivable \| Commercial \| Construction \| Adoption of CECL
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	(2,583)
Loans receivable \| Commercial \| Construction \| Adjusted Balance
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	7,085
Loans receivable \| Commercial \| Equipment financing
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	7,384	5,452
Allowance for credit losses - loans, Charge-Offs	(1,863)	(1,424)
Allowance for credit losses - loans, Recoveries	356	143
Allowance for credit losses - loans, (Release) Provision	2,990	2,060
Allowance for credit losses - loans, Ending Balance	14,738	6,231
Loans receivable \| Commercial \| Equipment financing \| Adoption of CECL
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	5,871
Loans receivable \| Commercial \| Equipment financing \| Adjusted Balance
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	13,255
Loans receivable \| Residential \| Construction
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	2,504	2,433
Allowance for credit losses - loans, Charge-Offs	(22)	(4)
Allowance for credit losses - loans, Recoveries	34	26
Allowance for credit losses - loans, (Release) Provision	71	(65)
Allowance for credit losses - loans, Ending Balance	816	2,390
Loans receivable \| Residential \| Construction \| Adoption of CECL
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	(1,771)
Loans receivable \| Residential \| Construction \| Adjusted Balance
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	733
Loans receivable \| Residential \| Residential mortgage
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	8,081	8,295
Allowance for credit losses - loans, Charge-Offs	(284)	(61)
Allowance for credit losses - loans, Recoveries	275	48
Allowance for credit losses - loans, (Release) Provision	1,422	63
Allowance for credit losses - loans, Ending Balance	11,063	8,345
Loans receivable \| Residential \| Residential mortgage \| Adoption of CECL
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	1,569
Loans receivable \| Residential \| Residential mortgage \| Adjusted Balance
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	9,650
Loans receivable \| Residential \| Home equity lines of credit
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	4,575	4,752
Allowance for credit losses - loans, Charge-Offs	(20)	(337)
Allowance for credit losses - loans, Recoveries	103	122
Allowance for credit losses - loans, (Release) Provision	310	260
Allowance for credit losses - loans, Ending Balance	6,887	4,797
Loans receivable \| Residential \| Home equity lines of credit \| Adoption of CECL
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	1,919
Loans receivable \| Residential \| Home equity lines of credit \| Adjusted Balance
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	6,494
Loans receivable \| Consumer
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	901	853
Allowance for credit losses - loans, Charge-Offs	(638)	(547)
Allowance for credit losses - loans, Recoveries	231	207
Allowance for credit losses - loans, (Release) Provision	427	324
Allowance for credit losses - loans, Ending Balance	430	$ 837
Loans receivable \| Consumer \| Adoption of CECL
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	(491)
Loans receivable \| Consumer \| Adjusted Balance
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	$ 410

Financing Receivable Allowance For Credit Loss And Off-Balance Sheet Credit Loss Liability

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Financing Receivable Allowance For Credit Loss And Off-Balance Sheet Credit Loss Liability, Recovery

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Financing Receivable Allowance For Credit Loss And Off-Balance Sheet Credit Loss Liability, Writeoff

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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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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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