Derivative Instruments (Details 4) (Cash Flow Hedging, USD $)	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Effects of derivative instruments
Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion)	$ 1,690,000	$ 508,000	$ 1,933,000
Amount of Loss (Gain) Reclassified from Accumulated OCI into Income (Effective Portion)	1,485,000	6,427,000	11,349,000
Significant ineffectiveness on hedges	0	0	0
Interest expense
Effects of derivative instruments
Amount of Loss (Gain) Reclassified from Accumulated OCI into Income (Effective Portion)	1,485,000	6,427,000	11,349,000
Interest rate contracts
Effects of derivative instruments
Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion)	1,690,000	508,000	1,933,000
Amount of interest payments reclassified to income statement	$ 1,900,000	$ 6,700,000	$ 10,900,000

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The effective portion of gains and losses (net) 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 Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (b)

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

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Represents the portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing the amount of significant hedge ineffectiveness.

+ References

No definition available.

+ Details

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- Definition

Represents the interest payments reclassified to income on derivative instruments.

+ References

No definition available.

+ Details

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