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=84173941&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=84173941&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=84173941&loc=SL6953423-111524

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ 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=84173941&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=84173941&loc=SL6953423-111524

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- Definition

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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Allowance For Loan Losses And Credit Quality Of Financing Receivables - Allowances Of Loan Losses And Loans Receivable By Class Disaggregated (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, Allowance for Loan Losses	$ 7,165	$ 6,797	$ 6,696	$ 5,988	$ 5,812	$ 5,590
Allowance for Loan Losses, Balance Related to Loans Individually Evaluated for Impairment	28		155
Allowance for Loan Losses, Balance Related to Loans Collectively Evaluated for Impairment	5,837		5,164
Total Financing Receivables	773,217		696,142
Loans Receivable, Individually Evaluated for Impairment	6,567		6,597
Loans Receivable, Collectively Evaluated for Impairment	766,650		689,545
Commercial And Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, Allowance for Loan Losses	201	92	110	199	98	85
Allowance for Loan Losses, Balance Related to Loans Individually Evaluated for Impairment	0		14
Allowance for Loan Losses, Balance Related to Loans Collectively Evaluated for Impairment	201		96
Total Financing Receivables	40,802		40,280
Loans Receivable, Individually Evaluated for Impairment	20		33
Loans Receivable, Collectively Evaluated for Impairment	40,782		40,247
Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, Allowance for Loan Losses	478	425	359	208	267	220
Allowance for Loan Losses, Balance Related to Loans Individually Evaluated for Impairment	0		0
Allowance for Loan Losses, Balance Related to Loans Collectively Evaluated for Impairment	478		359
Total Financing Receivables	41,213		25,360
Loans Receivable, Individually Evaluated for Impairment	0		0
Loans Receivable, Collectively Evaluated for Impairment	41,213		25,360
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, Allowance for Loan Losses	4,243	4,025	3,932	4,020	3,847	3,646
Allowance for Loan Losses, Balance Related to Loans Individually Evaluated for Impairment	28		135
Allowance for Loan Losses, Balance Related to Loans Collectively Evaluated for Impairment	4,221		3,797
Total Financing Receivables	526,054		479,227
Loans Receivable, Individually Evaluated for Impairment	4,509		4,597
Loans Receivable, Collectively Evaluated for Impairment	521,545		474,630
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, Allowance for Loan Losses	917	925	899	914	908	784
Allowance for Loan Losses, Balance Related to Loans Individually Evaluated for Impairment	0		6
Allowance for Loan Losses, Balance Related to Loans Collectively Evaluated for Impairment	917		893
Total Financing Receivables	164,181		150,237
Loans Receivable, Individually Evaluated for Impairment	2,038		1,967
Loans Receivable, Collectively Evaluated for Impairment	162,143		148,270
Consumer And Other [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, Allowance for Loan Losses	20	17	19	17	121	87
Allowance for Loan Losses, Balance Related to Loans Individually Evaluated for Impairment	0		0
Allowance for Loan Losses, Balance Related to Loans Collectively Evaluated for Impairment	20		19
Total Financing Receivables	967		1,038
Loans Receivable, Individually Evaluated for Impairment	0		0
Loans Receivable, Collectively Evaluated for Impairment	967		1,038
Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, Allowance for Loan Losses	1,306	$ 1,313	1,377	$ 630	$ 571	$ 768
Total Financing Receivables	$ 0		$ 0