Derivative Instruments Derivative Instruments (Derivative Assets Offset in The Consolidated Balance Sheet) (Details) - Interest Rate Swap $ in Thousands	Dec. 31, 2017 USD ($)
Customer Counterparties Loan Interest Rate Swap Assets \| Not Designated as Hedging Instrument
Offsetting Assets [Line Items]
Gross Amounts of Recognized Assets	$ 4,877
Derivative assets	4,877
Derivative Asset, Fair Value of Collateral	4,877
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	4,877
Derivative Asset, Fair Value, Amount Offset Against Collateral	0
Financial Institution Counterparties Loan Interest Rate Swap Asset \| Not Designated as Hedging Instrument
Offsetting Assets [Line Items]
Gross Amounts of Recognized Assets	9,591
Derivative assets	9,591
Derivative Asset, Fair Value of Collateral	0
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	0
Derivative Asset, Fair Value, Amount Offset Against Collateral	9,591
Financial Institution Counterparties Loan Interest Rate Swap Asset \| Designated as Hedging Instrument
Offsetting Assets [Line Items]
Gross Amounts of Recognized Assets	34
Derivative assets	34
Derivative Asset, Fair Value of Collateral	56
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	56
Derivative Asset, Fair Value, Amount Offset Against Collateral	$ 0

Fair value of securities received as collateral against derivative assets.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226013-175313

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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-Publisher FASB
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section 55
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-URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226008-175313

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Fair value, after effects of master netting arrangements, of 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 offset against an obligation to return collateral. 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
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No definition available.

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