Past Due Loans, Allowance For Credit Losses, Impaired Loans, and TDRs (Details) - TDRs That Defaulted Within Twelve Months of the Restructured Date $ in Thousands	12 Months Ended
Dec. 31, 2016 USD ($) loan	Dec. 31, 2015 USD ($) loan	Dec. 31, 2014 USD ($) loan
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	1	0	3
Recorded Investment \| $	$ 119	$ 0	$ 202
Commercial, industrial, and agricultural \| Commercial and industrial
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	0	0	2
Recorded Investment \| $	$ 0	$ 0	$ 125
Consumer loans \| Home equity
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	1	0	1
Recorded Investment \| $	$ 119	$ 0	$ 77

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953682-111524

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- Definition

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

+ References

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