Amount of direct write-downs of financing receivables charged against the allowance.

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)(3)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

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Number of financing receivables that have been modified by troubled debt restructurings.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18845-111554

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Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

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-Name Accounting Standards Codification
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Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Allowance for Credit Losses (Narrative) (Details) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($) loan	Jun. 30, 2016 USD ($)	Dec. 31, 2016 USD ($) loan
Financing Receivable, Modifications [Line Items]
Number of TDR loans \| loan			5		5
TDR recorded investment	$ 895		$ 895		$ 914
Partial charge-off of loan amount	740	$ 133	$ 1,089	$ 230
Number of defaulted TDRs \| loan			0		0
Loan defaults on TDRs			$ 0	$ 0
Accruing Impaired Home Equity Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of TDR loans \| loan			1		1
TDR recorded investment	102		$ 102		$ 102
Nonaccrual Impaired Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of TDR loans \| loan			4		4
TDR recorded investment	793		$ 793		$ 812
Residential Mortgage [Member]
Financing Receivable, Modifications [Line Items]
Number of TDR loans \| loan			2		2
Partial charge-off of loan amount			$ 151		$ 151
Real estate loans in process of foreclosure	479		$ 479		$ 0
Consumer Installment Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of TDR loans \| loan			1		1
Partial charge-off of loan amount			$ 2		$ 2
Other Real Estate Owned [Member]
Financing Receivable, Modifications [Line Items]
Real estate loans in process of foreclosure	$ 92		$ 92		$ 170