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

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

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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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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)	3 Months Ended		9 Months Ended		12 Months Ended
Allowance for Credit Losses (Narrative) (Details)	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) loan item	Sep. 30, 2018 USD ($) loan	Dec. 31, 2018 USD ($) loan
Financing Receivable, Modifications [Line Items]
Number of TDR loans \| loan			15		9
TDR recorded investment	$ 3,613,000		$ 3,613,000		$ 1,762,000
Partial charge-off of loan amount	152,000	$ 38,000	$ 493,000	$ 472,000
Number of defaulted TDRs \| loan			0		0
Loan defaults on TDRs					$ 0
Accruing Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of TDR loans \| loan					9
Accruing Impaired Home Equity Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of TDR loans \| loan			8
Nonaccrual Impaired Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of TDR loans \| loan			7
Residential Mortgage [Member]
Financing Receivable, Modifications [Line Items]
Real estate loans in process of foreclosure	343,000		$ 343,000		$ 0
Number of TDR loans \| loan					2
TDR recorded investment	2,091,000		2,091,000		$ 630,000
Partial charge-off of loan amount	125,000		$ 125,000	$ 137,000	$ 151,000
Number of defaulted TDRs \| item			2
Consumer Installment Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of TDR loans \| loan			1		1
Partial charge-off of loan amount			$ 2,000		$ 2,000
Other Real Estate Owned [Member]
Financing Receivable, Modifications [Line Items]
Real estate loans in process of foreclosure	140,000		$ 140,000		$ 97,000
Commercial Term Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of TDR loans \| loan			4
TDR recorded investment	421,000		$ 421,000
Commercial Mortgage [Member]
Financing Receivable, Modifications [Line Items]
Number of TDR loans \| loan				1	1
TDR recorded investment	945,000	$ 73,000	945,000	$ 73,000	$ 962,000
Partial charge-off of loan amount			$ 105,000	$ 184,000
Two Residential Mortgage [Member]
Financing Receivable, Modifications [Line Items]
Number of TDR loans \| loan			2
TDR recorded investment	$ 1,500,000		$ 1,500,000
Partial charge-off of loan amount			$ 151,000
One Residential Mortgage [Member]
Financing Receivable, Modifications [Line Items]
TDR recorded investment					$ 73,000