Derivative Financial Instruments Offsetting of Derivative Liabilities (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Offsetting Liabilities [Line Items]
Gross Amounts of Recognized Liabilities Presented in the Consolidated Balance Sheets	$ 1,590	$ 2,839
Derivative Financial Instruments Not Offset in the Consolidated Balance Sheets	(122)	(135)
Cash Collateral Pledged Not Offset in the Consolidated Balance Sheets	0	0
Net Amount	$ 1,468	$ 2,704

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 offset against the right to receive collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=20225523&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 13

-URI http://asc.fasb.org/extlink&oid=28370219&loc=SL20226016-175313

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=d3e41678-113959

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Data Type:	xbrli:monetaryItemType
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