Loans and Allowance for Loan Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 15,442	$ 14,999
Provision for loan losses	0	0
Charge-offs	(287)	(9)
Recoveries	64	38
Ending balance	15,219	15,028
Ending ALLL related to loans collectively evaluated for impairment	14,546		$ 14,451
Ending ALLL related to loans individually evaluated for impairment	673		991
Ending ALLL related to purchased credit-impaired loans	15,219		15,442
Collectively evaluated for impairment	1,456,178		1,465,383
Individually evaluated for impairment	18,455		18,313
Total loans	$ 1,477,570		$ 1,486,616
Ratio of allowance for loan losses to total loans	1.03%		1.04%
Allowance for loan losses to non-accrual loans	1253.00%		10650.00%
Purchase credit-impaired
Allowance for Loan and Lease Losses [Roll Forward]
Ending ALLL related to purchased credit-impaired loans	$ 0		$ 0
Purchase credit-impaired	2,937		2,920
Commercial loans \| Commercial and industrial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	3,248	3,023
Provision for loan losses	1,386	(247)
Charge-offs	(284)	(9)
Recoveries	63	32
Ending balance	4,413	2,799
Ending ALLL related to loans collectively evaluated for impairment	4,385		2,963
Ending ALLL related to loans individually evaluated for impairment	28		285
Ending ALLL related to purchased credit-impaired loans	4,413		3,248
Collectively evaluated for impairment	217,649		216,368
Individually evaluated for impairment	2,070		2,207
Total loans	$ 219,760		$ 218,615
Ratio of allowance for loan losses to total loans	2.01%		1.49%
Commercial loans \| Commercial and industrial \| Purchase credit-impaired
Allowance for Loan and Lease Losses [Roll Forward]
Ending ALLL related to purchased credit-impaired loans	$ 0		$ 0
Purchase credit-impaired	41		40
Commercial real estate loans \| Commercial real estate, owner-occupied
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,753	2,249
Provision for loan losses	239	(630)
Charge-offs	0	0
Recoveries	0	0
Ending balance	1,992	1,619
Ending ALLL related to loans collectively evaluated for impairment	1,835		1,590
Ending ALLL related to loans individually evaluated for impairment	157		163
Ending ALLL related to purchased credit-impaired loans	1,992		1,753
Collectively evaluated for impairment	246,086		239,648
Individually evaluated for impairment	7,001		6,993
Total loans	$ 254,180		$ 247,713
Ratio of allowance for loan losses to total loans	0.78%		0.71%
Commercial real estate loans \| Commercial real estate, owner-occupied \| Purchase credit-impaired
Allowance for Loan and Lease Losses [Roll Forward]
Ending ALLL related to purchased credit-impaired loans	$ 0		$ 0
Purchase credit-impaired	1,093		1,072
Commercial real estate loans \| Commercial real estate, investor
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	6,320	6,178
Provision for loan losses	(187)	388
Charge-offs	0	0
Recoveries	0	5
Ending balance	6,133	6,571
Ending ALLL related to loans collectively evaluated for impairment	5,759		5,945
Ending ALLL related to loans individually evaluated for impairment	374		375
Ending ALLL related to purchased credit-impaired loans	6,133		6,320
Collectively evaluated for impairment	707,070		720,266
Individually evaluated for impairment	3,311		2,256
Total loans	$ 712,081		$ 724,228
Ratio of allowance for loan losses to total loans	0.86%		0.87%
Allowance for loan losses to non-accrual loans	570.00%
Commercial real estate loans \| Commercial real estate, investor \| Purchase credit-impaired
Allowance for Loan and Lease Losses [Roll Forward]
Ending ALLL related to purchased credit-impaired loans	$ 0		$ 0
Purchase credit-impaired	1,700		1,706
Commercial real estate loans \| Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	781	724
Provision for loan losses	(235)	98
Charge-offs	0	0
Recoveries	0	0
Ending balance	546	822
Ending ALLL related to loans collectively evaluated for impairment	540		773
Ending ALLL related to loans individually evaluated for impairment	6		8
Ending ALLL related to purchased credit-impaired loans	546		781
Collectively evaluated for impairment	63,921		71,564
Individually evaluated for impairment	3,241		3,245
Total loans	$ 67,162		$ 74,809
Ratio of allowance for loan losses to total loans	0.81%		1.04%
Commercial real estate loans \| Construction \| Purchase credit-impaired
Allowance for Loan and Lease Losses [Roll Forward]
Ending ALLL related to purchased credit-impaired loans	$ 0		$ 0
Purchase credit-impaired	0		0
Residential loans \| Home equity
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	973	910
Provision for loan losses	17	133
Charge-offs	0	0
Recoveries	0	1
Ending balance	990	1,044
Ending ALLL related to loans collectively evaluated for impairment	980		966
Ending ALLL related to loans individually evaluated for impairment	10		7
Ending ALLL related to purchased credit-impaired loans	990		973
Collectively evaluated for impairment	114,366		116,390
Individually evaluated for impairment	711		715
Total loans	$ 115,180		$ 117,207
Ratio of allowance for loan losses to total loans	0.86%		0.83%
Allowance for loan losses to non-accrual loans	1138.00%		1071.00%
Residential loans \| Home equity \| Purchase credit-impaired
Allowance for Loan and Lease Losses [Roll Forward]
Ending ALLL related to purchased credit-impaired loans	$ 0		$ 0
Purchase credit-impaired	103		102
Residential loans \| Other residential
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	454	394
Provision for loan losses	(10)	36
Charge-offs	0	0
Recoveries	0	0
Ending balance	444	430
Ending ALLL related to loans collectively evaluated for impairment	444		399
Ending ALLL related to loans individually evaluated for impairment	0		55
Ending ALLL related to purchased credit-impaired loans	444		454
Collectively evaluated for impairment	83,545		76,584
Individually evaluated for impairment	1,175		1,965
Total loans	$ 84,720		$ 78,549
Ratio of allowance for loan losses to total loans	0.52%		0.58%
Residential loans \| Other residential \| Purchase credit-impaired
Allowance for Loan and Lease Losses [Roll Forward]
Ending ALLL related to purchased credit-impaired loans	$ 0		$ 0
Purchase credit-impaired	0		0
Consumer loans \| Installment and other consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	372	425
Provision for loan losses	(11)	9
Charge-offs	(3)	0
Recoveries	1	0
Ending balance	359	434
Ending ALLL related to loans collectively evaluated for impairment	261		274
Ending ALLL related to loans individually evaluated for impairment	98		98
Ending ALLL related to purchased credit-impaired loans	359		372
Collectively evaluated for impairment	23,541		24,563
Individually evaluated for impairment	946		932
Total loans	$ 24,487		$ 25,495
Ratio of allowance for loan losses to total loans	1.47%		1.46%
Allowance for loan losses to non-accrual loans	690.00%		683.00%
Consumer loans \| Installment and other consumer \| Purchase credit-impaired
Allowance for Loan and Lease Losses [Roll Forward]
Ending ALLL related to purchased credit-impaired loans	$ 0		$ 0
Purchase credit-impaired	0		0
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,541	1,096
Provision for loan losses	(1,199)	213
Charge-offs	0	0
Recoveries	0	0
Ending balance	342	$ 1,309
Ending ALLL related to loans collectively evaluated for impairment	342		1,541
Ending ALLL related to loans individually evaluated for impairment	0		0
Ending ALLL related to purchased credit-impaired loans	342		1,541
Collectively evaluated for impairment	0		0
Individually evaluated for impairment	0		0
Total loans	0		0
Unallocated \| Purchase credit-impaired
Allowance for Loan and Lease Losses [Roll Forward]
Ending ALLL related to purchased credit-impaired loans	0		0
Purchase credit-impaired	$ 0		$ 0

Allowance as percentage of non-accrual loans.

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Allowance as percentage of total loans.

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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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A valuation allowance for financing receivables that are expected to be uncollectible.

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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.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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