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
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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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The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

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-Name Accounting Standards Codification
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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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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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Allowance for Credit Losses (Narrative) (Details) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2017 USD ($) loan	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) loan	Sep. 30, 2016 USD ($)	Dec. 31, 2016 USD ($) loan
Financing Receivable, Modifications [Line Items]
Number of TDR loans \| loan			8		5
TDR recorded investment	$ 1,872		$ 1,872		$ 914
Partial charge-off of loan amount	50	$ 47	$ 1,139	$ 277
Number of defaulted TDRs \| loan			0		0
Loan defaults on TDRs			$ 0	$ 0
Accruing Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of TDR loans \| loan			5
TDR recorded investment	1,134		$ 1,134
Accruing Impaired Home Equity Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of TDR loans \| loan					1
TDR recorded investment					$ 102
Nonaccrual Impaired Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of TDR loans \| loan			3		4
TDR recorded investment	738		$ 738		$ 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	642		$ 642		$ 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	$ 74		$ 74		$ 170
Commercial Mortgage [Member]
Financing Receivable, Modifications [Line Items]
Number of TDR loans \| loan	3		3
TDR recorded investment	$ 987		$ 987