Derivative Instruments Derivative Instruments (Balance Sheet Offsetting) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Derivative Asset, Amount Offset by Liabiilty	$ 0	$ 0
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	13,230	10,457
Derivative Assets	13,230us-gaap_DerivativeAssets	10,457us-gaap_DerivativeAssets
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	13,782	10,948
Derivative Liability, Amount Offset by Asset	0	0
Derivative Liabilities	13,782us-gaap_DerivativeLiabilities	10,948us-gaap_DerivativeLiabilities
Derivative Subject to Master Netting Agreement [Member]
Derivative Asset, Fair Value, Gross Asset	12,667	10,209
Derivative Asset, Amount Offset by Liabiilty	0	0
Derivative Asset, Net Amount Presented in the Balance Sheet	12,667	10,209
Derivative Asset, Not Offset, Policy Election Deduction	(49)	(251)
derivatve asset, fair value of collateral	0	0
Derivative Asset, Fair Value, Amount Offset Against Collateral	12,618	9,958
Derivative Liability, Fair Value, Gross Liability	12,940	10,454
Derivative Liability, Net Amount Presented in the Balance Sheet	12,940	10,454
Derivative Liability, Not Offset, Policy Election Deduction	(49)	(251)
Derivative Liability, Fair Value of Collateral	(11,576)	(8,738)
Derivative Liability, Fair Value, Amount Offset Against Collateral	1,315	1,465
Derivative Liability, Amount Offset by Asset	0	0
Derivative Not Subject to Master Netting Agreement [Member]
Derivative Asset, Fair Value, Gross Asset	563	248
Derivative Asset, Amount Offset by Liabiilty	0	0
Derivative Asset, Not Subject to Master Netting Arrangement	563	248
Derivative Liability, Fair Value, Gross Liability	842	494
Derivative, Fair Value, Net	842	494
Derivative Liability, Amount Offset by Asset	$ 0	$ 0

Amount of the liability offset against the fair value of gross derivative assets on the balance sheet.

No definition available.

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Data Type:	xbrli:monetaryItemType
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- Definition

Amount of the asset offset against the fair value of gross derivative liabilities on the balance sheet.

+ References

No definition available.

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- Definition

Fair value of securities received as collateral against derivative assets.

+ References

No definition available.

+ Details

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- Definition

Fair value, before 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 elected not to be offset.

+ References

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- Definition

Fair value 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, elected not to be offset, deducted from derivative assets.

+ References

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- Definition

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 22

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-Paragraph 3

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- Definition

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

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+ Details

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- Definition

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, expected to be settled after one year or the normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

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- Definition

Fair value, before 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 elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ 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 (a)

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- Definition

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

-Topic 210

-SubTopic 20

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-Paragraph 13

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- Definition

Fair value, before 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 elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

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- Definition

Fair value, after effects of master netting arrangements, of 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 offset against the right to receive collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

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- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

+ Details

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- Definition

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

+ Details

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- Definition

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, expected to be settled after one year or the normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

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- Definition

Fair value, before 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 elected not to be offset.

+ References

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- Definition

Fair value of securities pledged as collateral against derivative liabilities.

+ References

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=36459792&loc=SL20226013-175313

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- Definition

Fair value of 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, elected not to be offset, deducted from derivative liabilities.

+ References

+ Details

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