Loans - Changes in the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Changes in the Allowance for Loan Losses
Balance, beginning of period	$ 19,458	$ 18,554	$ 18,926	$ 18,379
Charge-offs	(23)	(9)	(140)	(223)
Recoveries	135	190	383	639
Net recoveries	112	181	243	416
Provision (credit) for loan losses	351	22	752	(38)
Balance, end of period	19,921	18,757	19,921	18,757
Commercial
Changes in the Allowance for Loan Losses
Balance, beginning of period	11,279	10,856	10,748	11,187
Charge-offs	(23)	(9)	(140)	(221)
Recoveries	129	46	161	482
Net recoveries	106	37	21	261
Provision (credit) for loan losses	143	300	759	(255)
Balance, end of period	11,528	11,193	11,528	11,193
Real estate
Changes in the Allowance for Loan Losses
Balance, beginning of period	8,068	7,554	8,076	7,070
Charge-offs				(2)
Recoveries	6	114	222	127
Net recoveries	6	114	222	125
Provision (credit) for loan losses	203	(218)	(21)	255
Balance, end of period	8,277	7,450	8,277	7,450
Consumer
Changes in the Allowance for Loan Losses
Balance, beginning of period	111	144	102	122
Recoveries		30		30
Net recoveries		30		30
Provision (credit) for loan losses	5	(60)	14	(38)
Balance, end of period	$ 116	$ 114	$ 116	$ 114

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.

+ References

No definition available.

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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, after recoveries, of loans and leases that have been written-off.

+ References

No definition available.

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 6
-Section L
-Subsection 1

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
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