Accounting for Derivatives (Details 2) (Interest rate hedges, Derivatives designated as cash flow hedges, USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Interest rate hedges \| Derivatives designated as cash flow hedges
Effect of derivative instruments on results of operations
Pre-tax Gain (Loss) Recognized in Other Comprehensive Income (Loss) on Derivatives	$ (2,247)	$ (1,446)	$ 2,453	$ (5,827)
Pre-tax Gain (Loss) Reclassified from Accumulated Other Comprehensive Income (loss) into Income (Loss)	$ (1,332)	$ (5,111)	$ (4,805)	$ (24,712)

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4D

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624177-113959

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