Derivative Instruments and Hedging Activities (Schedule of Derivative Instruments in Consolidated Statements of Operations) (Details) (Cash Flow Interest Rate Contracts [Member], USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2011	Sep. 30, 2010
(Gain)/loss recognized in OCI (effectiveness)	$ 17,325	$ 4,495	$ 26,972	$ 15,172
Loss recognized due to ineffectiveness	0	0	0	0
Interest Expense [Member]
Loss reclassified from OCI into income	$ 3,510	$ 764	$ 10,559	$ 842

The portion of losses on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 205G

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 25

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5624171-113959

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44C

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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