Allowance for Loan and Lease Losses - Schedule of Detail in Allowance for Loan and Lease Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance			$ 39,771
Provision (credit)	$ 272	$ 402	1,884	$ 2,147
Ending Balance	41,358		41,358
Originated Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	41,111	36,960	39,686	35,598
Charge-offs	(344)	(338)	(1,658)	(1,408)
Recoveries	314	350	1,410	1,334
Provision (credit)	208	931	1,851	2,379
Ending Balance	41,289	37,903	41,289	37,903
Total Acquired Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	114	197	85	157
Charge-offs	(168)	(45)	(272)	(345)
Recoveries	59	512	223	555
Provision (credit)	64	(529)	33	(232)
Ending Balance	69	135	69	135
Commercial and industrial \| Originated Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	12,866	10,842	11,812	9,389
Charge-offs	(118)	(85)	(224)	(162)
Recoveries	8	(18)	16	112
Provision (credit)	(335)	951	817	2,351
Ending Balance	12,421	11,690	12,421	11,690
Commercial and industrial \| Total Acquired Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	19	50	25	0
Charge-offs	(42)	0	(43)	(74)
Recoveries	32	0	88	0
Provision (credit)	(9)	(50)	(70)	74
Ending Balance	0	0	0	0
Commercial real estate \| Originated Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	20,770	19,121	20,412	19,836
Charge-offs	0	0	(60)	(21)
Recoveries	203	264	549	717
Provision (credit)	199	70	271	(1,077)
Ending Balance	21,172	19,455	21,172	19,455
Commercial real estate \| Total Acquired Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	25	87	0	97
Charge-offs	(81)	(10)	(81)	(84)
Recoveries	4	499	27	524
Provision (credit)	52	(501)	54	(462)
Ending Balance	0	75	0	75
Residential real estate \| Originated Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	6,147	5,761	6,161	5,149
Charge-offs	(2)	(41)	(208)	(483)
Recoveries	96	33	232	169
Provision (credit)	204	(262)	260	656
Ending Balance	6,445	5,491	6,445	5,491
Residential real estate \| Total Acquired Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	65	54	54	54
Charge-offs	(45)	(34)	(148)	(186)
Recoveries	23	12	106	24
Provision (credit)	21	22	52	162
Ending Balance	64	54	64	54
Consumer and other \| Originated Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,328	1,236	1,301	1,224
Charge-offs	(224)	(212)	(1,166)	(742)
Recoveries	7	71	613	336
Provision (credit)	140	172	503	449
Ending Balance	1,251	1,267	1,251	1,267
Consumer and other \| Total Acquired Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	5	6	6	6
Charge-offs	0	(1)	0	(1)
Recoveries	0	1	2	7
Provision (credit)	0	0	(3)	(6)
Ending Balance	5	6	5	6
Finance Leases \| Originated Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	0	0	0	0
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision (credit)	0	0	0	0
Ending Balance	0	0	0	0
Finance Leases \| Total Acquired Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	0	0	0	0
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision (credit)	0	0	0	0
Ending Balance	$ 0	$ 0	$ 0	$ 0

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

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

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

+ References

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

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

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