| **Derivative Instruments and Hedging Activities (Tables)**                             | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
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| **Derivative Instruments and Hedging Activities Disclosure [Abstract]**                |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| Fair Value of Derivative Financial Instruments and Classification on the Balance Sheet | The table below presents the fair value of the Corporation’s derivative financial instruments as well as their classification on the Balance Sheet as of December 31, 2016 and December 31, 2015. Asset DerivativesLiability Derivatives December 31, 2016December 31, 2015December 31, 2016December 31, 2015 Balance Sheet LocationFairValueBalance Sheet LocationFairValueBalance Sheet LocationFairValueBalance Sheet LocationFairValueDerivatives designated as hedging instruments:        Interest rate contractsOther Assets$15Other Assets$36Other Liabilities$2,182Other Liabilities$2,921Derivatives not designated as hedging instruments:        Interest rate contractsOther Assets$6,295Other Assets$4,938Other Liabilities$6,295Other Liabilities$5,149                                                                                                                                                                                                                                                                 |
| Effect of Derivative Financial Instruments on the Income Statement                     | The amount of gain (loss) recognized in other comprehensive income is included in the table below for the periods indicated.Derivatives in Cash Flow Hedging RelationshipsAmount of Gain (Loss) Recognized in Other Comprehensive Income on Derivative (Effective Portion) For the Year Ended20162015Interest rate products$(368)$(1,681)Effect of Derivative Instruments on the Income StatementThe tables below present the effect of the Corporation’s derivative financial instruments on the Income Statement for the years ended December 31, 2016, 2015 and 2014.Derivatives NotDesignated as HedgingInstruments underFASB ASC 815-10Location of Gain(Loss) Recognized inIncome on DerivativeAmount of Gain (Loss) Recognized in Income on Derivative201620152014Interest rate contractsOther income$211$(53)$(73)Derivatives Designated as HedgingInstruments underFASB ASC 815-10Location of Loss Reclassified from Accumulated Other Comprehensive Income (Effective Portion)Amount of Loss Reclassified from Other Comprehensive Income into Income (Effective Portion) 201620152014Interest rate contractsInterest expense$(1,250)$(1,427)$(1,411) |

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| - Definition
Tabular disclosure of the location and amount of derivative instruments and nonderivative instruments designated as hedging instruments reported before netting adjustments, and the amount of gain (loss) on derivative instruments and nonderivative instruments designated and qualified as hedging instruments.
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Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5618551-113959
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| - Definition
Tabular disclosure of the location and fair value amounts of derivative instruments (and nonderivative instruments that are designated and qualify as hedging instruments) reported in the statement of financial position.
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Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624163-113959
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