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

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

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ 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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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ 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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- 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

The balance of financing receivables that were collectively evaluated for impairment.

+ 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 (h)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

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- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ 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 (h)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5074-111524

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- References

No definition available.

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Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Loans, net and allowance for loan losses - Allocation of Allowance for Loan Losses and Related Loans by Major Classification of Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016	Dec. 31, 2015
Allowance for loan losses:
Ending balance	$ 16,969	$ 15,961	$ 14,158	$ 12,975
Ending balance: individually evaluated for impairment	1,424	1,942
Ending balance: collectively evaluated for impairment	15,545	14,019
Loans receivable:
Ending balance	1,559,867	1,532,965
Ending balance: individually evaluated for impairment	9,726	11,242
Ending balance: collectively evaluated for impairment	1,548,393	1,519,386
Loans Acquired with Deteriorated Credit Quality
Loans receivable:
Ending balance	1,748	2,337
Commercial
Allowance for loan losses:
Ending balance	4,129	3,799	3,322	3,042
Ending balance: individually evaluated for impairment	404	225
Ending balance: collectively evaluated for impairment	3,725	3,574
Loans receivable:
Ending balance	431,164	408,814
Ending balance: individually evaluated for impairment	2,311	1,724
Ending balance: collectively evaluated for impairment	428,476	406,127
Commercial \| Loans Acquired with Deteriorated Credit Quality
Loans receivable:
Ending balance	377	963
Real estate Commercial
Allowance for loan losses:
Ending balance	6,291	5,847	4,616	4,245
Ending balance: individually evaluated for impairment	513	1,197
Ending balance: collectively evaluated for impairment	5,778	4,650
Loans receivable:
Ending balance	703,194	700,144
Ending balance: individually evaluated for impairment	3,849	5,820
Ending balance: collectively evaluated for impairment	698,008	692,987
Real estate Commercial \| Loans Acquired with Deteriorated Credit Quality
Loans receivable:
Ending balance	1,337	1,337
Real estate Residential
Loans receivable:
Ending balance	286,389	289,781
Consumer
Allowance for loan losses:
Ending balance	1,571	1,608	1,646	1,583
Ending balance: individually evaluated for impairment	23
Ending balance: collectively evaluated for impairment	1,548	1,608
Loans receivable:
Ending balance	139,120	134,226
Ending balance: individually evaluated for impairment	207	155
Ending balance: collectively evaluated for impairment	$ 138,913	$ 134,071
Unallocated
Allowance for loan losses:
Ending balance			$ 215	$ 23