Fair Value Measurements (Details 4) (USD $)	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Derivative financial instruments related to unconsolidated joint venture
Number of derivative agreements for which the Parent Company could be liable in event of default by a subsidiary	1
Cash flow hedges
Reclassification of gain (loss)
Gain or loss recognized with respect to cash flow hedges' ineffectiveness	$ 0	$ 0
Interest rate swap \| Cash flow hedges
Fair Value Measurements
Amount of loss gain recognized on derivative in Other comprehensive loss	(1,623,000)	(1,106,000)
Amount of loss reclassification from Accumulated other comprehensive loss into Interest expense	(889,000)	(388,000)
Reclassification of gain (loss)
Number of interest rate derivative instruments terminated	1
Accelerated amount of loss	472,000
Additional amount to be reclassified to interest expense during the next twelve months	1,526,000
Credit risk related contingent feature
Fair value of derivative in a liability position, including accrued interest and excluding adjustments for nonperformance risk	4,209,000
Termination value of derivative agreement	4,209,000
Adjustments for nonperformance risk	358,000
Interest rate swap \| Cash flow hedges \| Accrued Expenses And Other Liabilities
Credit risk related contingent feature
Termination value of derivative agreement	3,851,000
Interest rate swap \| Cash flow hedges \| Unconsolidated JV
Fair Value Measurements
Number of unconsolidated joint ventures of the entity with interest rate derivatives outstanding	3
Percentage of ownership in unconsolidated joint venture	50.00%
Number interest rate derivatives outstanding	2
Notional Amount	11,166,000
Amount of loss gain recognized on derivative in Other comprehensive loss	(71,000)	(7,000)
Amount of loss reclassification from Accumulated other comprehensive loss into Interest expense	$ (22,000)	$ (14,000)
Interest rate swap \| Cash flow hedges \| Unconsolidated JV \| Minimum
Fair Value Measurements
Fixed Interest Rate (as a percent)	3.49%
Interest rate swap \| Cash flow hedges \| Unconsolidated JV \| Maximum
Fair Value Measurements
Fixed Interest Rate (as a percent)	5.81%

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

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

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The number of derivative agreements for which the Parent Company could be liable in event of default by a subsidiary.

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Number of interest rate derivate instruments terminated by the entity at the reporting date.

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Represents the number of unconsolidated joint ventures of the entity had interest rate derivative outstanding at the reporting date.

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The aggregate fair value of assets needed to immediately settle the derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4H

-Subparagraph (f)

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The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (c)

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Fixed interest rate related to the interest rate derivative.

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

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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)

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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.

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The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4H

-Subparagraph (c)

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

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The net gain (loss) recognized in earnings during the reporting period representing the amount of the cash flow hedges' ineffectiveness.

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The loss recognized in earnings during the reporting period representing the amount of the cash flow hedges' ineffectiveness.

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Number of interest rate derivative instruments held by the entity at the reporting date.

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-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

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