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Derivative Instruments and Hedging Activities - Value of Derivative Assets and Derivative Liabilities (Details) - Not Designated as Hedging Instruments - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Derivatives not Designated as Hedging Instruments
Fair value, Derivatives (included in Other Assets)	$ 6,960	$ 11,295
Fair value, Derivatives (included in Other Liabilities)	6,958	11,276
Collateral posted, Derivatives (included in Other Liabilities)	14,340	12,573
Other Assets | Interest Rate Swap Contracts-Commercial Loans
Derivatives not Designated as Hedging Instruments
Fair value, Derivatives (included in Other Assets)	6,960	11,295
Notional amount, Derivatives (included in Other Assets)	232,396	245,595
Other Assets | Interest Rate Lock Commitments-Mortgage Loans
Derivatives not Designated as Hedging Instruments
Fair value, Derivatives (included in Other Assets)	236	261
Notional amount, Derivatives (included in Other Assets)	8,490	9,894
Other Assets | Forward Sale Contracts-Mortgage Loans
Derivatives not Designated as Hedging Instruments
Fair value, Derivatives (included in Other Assets)	0	0
Notional amount, Derivatives (included in Other Assets)	0	0
Other Liabilities | Interest Rate Swap Contracts-Commercial Loans
Derivatives not Designated as Hedging Instruments
Fair value, Derivatives (included in Other Liabilities)	6,958	11,276
Notional amount, Derivatives (included in Other Liabilities)	232,396	245,595
Collateral posted, Derivatives (included in Other Liabilities)	14,340	12,753
Other Liabilities | Forward Sale Contracts-Mortgage Loans
Derivatives not Designated as Hedging Instruments
Fair value, Derivatives (included in Other Liabilities)	27	5
Notional amount, Derivatives (included in Other Liabilities)	$ 8,216	$ 9,800

X

- Definition

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624258-113959

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- Definition

Nominal or face amount used to calculate payments on the derivative asset.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Notional Amount
-URI http://asc.fasb.org/extlink&oid=6519104

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-Name Accounting Standards Codification
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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

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-Topic 210
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Nominal or face amount used to calculate payments on the derivative liability.

+ References

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