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	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance			$ 62,089	$ 61,203
Allowance for credit losses - loans, Charge-Offs			(18,864)	(8,187)
Allowance for credit losses - loans, Recoveries			4,601	2,619
Allowance for credit losses - loans, (Release) Provision			48,963	6,569
Allowance for credit losses - loans, Ending Balance	$ 103,669	$ 62,204	103,669	62,204
Allowance for unfunded commitments, Beginning Balance	6,470	3,141	3,458	3,410
Allowance for unfunded commitments, (Release) Provision	5,630	250	6,771	(19)
Allowance for unfunded commitments, Ending Balance	12,100	3,391	12,100	3,391
Total allowance for credit losses, Beginning Balance	88,375	64,783	65,547	64,613
Total allowance for credit losses, Charge-Offs	(8,059)	(3,827)	(18,864)	(8,187)
Total allowance for credit losses, Recoveries	1,910	1,389	4,601	2,619
Total allowance for credit losses, (Release) Provision	33,543	3,250	55,734	6,550
Total allowance for credit losses, Ending Balance	115,769	65,595	115,769	65,595
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
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	81,905	61,642
Allowance for credit losses - loans, Charge-Offs	(8,059)	(3,827)
Allowance for credit losses - loans, Recoveries	1,910	1,389
Allowance for credit losses - loans, (Release) Provision	27,913	3,000
Allowance for credit losses - loans, Ending Balance	103,669	62,204	103,669	62,204
Loans receivable \| Indirect auto
Allowance for Credit Loss
Allowance for credit losses - loans, Beginning Balance	0	872	0	999
Allowance for credit losses - loans, Charge-Offs	0	(180)	0	(377)
Allowance for credit losses - loans, Recoveries	0	46	0	84
Allowance for credit losses - loans, (Release) Provision	0	36	0	68
Allowance for credit losses - loans, Ending Balance	0	774	0	774
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	11,000	11,874	11,404	12,207
Allowance for credit losses - loans, Charge-Offs	0	0	(6)	(5)
Allowance for credit losses - loans, Recoveries	466	58	1,500	127
Allowance for credit losses - loans, (Release) Provision	3,126	(387)	3,310	(784)
Allowance for credit losses - loans, Ending Balance	14,592	11,545	14,592	11,545
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	16,584	11,126	12,306	11,073
Allowance for credit losses - loans, Charge-Offs	(4,589)	(308)	(5,000)	(505)
Allowance for credit losses - loans, Recoveries	41	66	182	86
Allowance for credit losses - loans, (Release) Provision	9,663	136	14,241	366
Allowance for credit losses - loans, Ending Balance	21,699	11,020	21,699	11,020
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	10,831	4,895	5,266	4,802
Allowance for credit losses - loans, Charge-Offs	(254)	(1,416)	(7,815)	(2,935)
Allowance for credit losses - loans, Recoveries	291	275	667	438
Allowance for credit losses - loans, (Release) Provision	(2,279)	1,554	6,459	3,003
Allowance for credit losses - loans, Ending Balance	8,589	5,308	8,589	5,308
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	9,556	10,275	9,668	10,337
Allowance for credit losses - loans, Charge-Offs	(239)	(1)	(239)	(70)
Allowance for credit losses - loans, Recoveries	117	163	258	557
Allowance for credit losses - loans, (Release) Provision	5,080	(119)	7,410	(506)
Allowance for credit losses - loans, Ending Balance	14,514	10,318	14,514	10,318
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	14,738	6,231	7,384	5,452
Allowance for credit losses - loans, Charge-Offs	(2,085)	(1,010)	(3,948)	(2,434)
Allowance for credit losses - loans, Recoveries	420	121	776	264
Allowance for credit losses - loans, (Release) Provision	7,232	1,593	10,222	3,653
Allowance for credit losses - loans, Ending Balance	20,305	6,935	20,305	6,935
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	816	2,390	2,504	2,433
Allowance for credit losses - loans, Charge-Offs	(32)	(246)	(54)	(250)
Allowance for credit losses - loans, Recoveries	37	47	71	73
Allowance for credit losses - loans, (Release) Provision	1,176	174	1,247	109
Allowance for credit losses - loans, Ending Balance	1,997	2,365	1,997	2,365
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	11,063	8,345	8,081	8,295
Allowance for credit losses - loans, Charge-Offs	(50)	(108)	(334)	(169)
Allowance for credit losses - loans, Recoveries	56	234	331	282
Allowance for credit losses - loans, (Release) Provision	1,757	(181)	3,179	(118)
Allowance for credit losses - loans, Ending Balance	12,826	8,290	12,826	8,290
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	6,887	4,797	4,575	4,752
Allowance for credit losses - loans, Charge-Offs	(98)	(29)	(118)	(366)
Allowance for credit losses - loans, Recoveries	196	140	299	262
Allowance for credit losses - loans, (Release) Provision	1,702	(114)	2,012	146
Allowance for credit losses - loans, Ending Balance	8,687	4,794	8,687	4,794
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	430	837	901	853
Allowance for credit losses - loans, Charge-Offs	(712)	(529)	(1,350)	(1,076)
Allowance for credit losses - loans, Recoveries	286	239	517	446
Allowance for credit losses - loans, (Release) Provision	456	308	883	632
Allowance for credit losses - loans, Ending Balance	$ 460	$ 855	460	$ 855
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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Amount of increase in allowance for credit loss on financing receivable from recovery.

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Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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