v2.4.0.6

Derivative Instruments (Classification of Changes in Fair Value) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended			12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Jun. 29, 2011 Interest Rate Swap	Dec. 31, 2012 Designated as Hedging Instrument Included in interest expense Cash Flow Hedging Interest Rate Swap	Dec. 31, 2011 Designated as Hedging Instrument Included in interest expense Cash Flow Hedging Interest Rate Swap	Dec. 31, 2010 Designated as Hedging Instrument Included in interest expense Cash Flow Hedging Interest Rate Swap	Dec. 31, 2011 Not Designated as Hedging Instrument Fair Value Adjustments on Hedges and Derivative Contracts Cash Flow Hedging Interest Rate Swap	Dec. 31, 2010 Not Designated as Hedging Instrument Fair Value Adjustments on Hedges and Derivative Contracts Cash Flow Hedging Interest Rate Swap
Derivative [Line Items]
Aggregate notional amount of derivatives			$ 500,000
Gain recognized in OCI on derivative (effective portion)					0	16,356
Gain (loss) reclassified from AOCI into income (ineffective portion)				0	11,800	22,700	265	480
Amounts amortized through other comprehensive income related to derivatives previously de-designated as hedging instruments	$ 11,824	$ 4,580

X

- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

+ Details

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X

- Definition

The effective portion of gains on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44C

-Subparagraph b

-Clause 2

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=20435746&loc=SL7669646-108580



Reference 3: 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 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (b)

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

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X

- Definition

The portion of a hedge deemed to be ineffective that is reflected in current period results of operations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (d)(1)

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



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- Definition

The amount of net gains or losses on interest rate cash flow hedges reclassified during the period to earnings from accumulated other comprehensive income upon the hedged transaction affecting earnings.

+ References

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 Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 45

-Subparagraph b(1)

-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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