Derivative Financial Instruments (Details 3) (USD $)	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
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 derivatives \| Cash flow hedges
Derivative Financial Instruments
Amount of (loss) recognized on derivative in Other comprehensive (loss)	26,000	(117,000)
Amount of (loss) reclassification from Accumulated other comprehensive (loss) into interest expense/earnings	(152,000)	(106,000)
Reclassification of gain (loss)
Additional amount to be reclassified to interest expense during the next twelve months	593,000
Credit risk related contingent feature
Fair value of derivative including accrued interest and excluding adjustments for nonperformance risk	1,347,000
Termination value of derivative agreement	1,347,000
Interest rate derivatives \| Cash flow hedges \| Unconsolidated joint ventures
Derivative Financial Instruments
Amount of (loss) recognized on derivative in Other comprehensive (loss)	(4,000)	(3,000)
Amount of (loss) reclassification from Accumulated other comprehensive (loss) into interest expense/earnings	(14,000)	(14,000)
Derivative financial instruments related to unconsolidated joint venture
Number of unconsolidated joint ventures of the entity with interest rate derivatives outstanding	2
Percentage of ownership in unconsolidated joint venture	50.00%
Notional Amount	$ 3,857,000
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.

+ References

No definition available.

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

+ References

No definition available.

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- Definition

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 Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44D

-Subparagraph c

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

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- Definition

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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

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-Paragraph 1

-Subparagraph (c)

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- Definition

Fixed interest rate related to the interest rate derivative.

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- Definition

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

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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- Definition

The effective portion of losses 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

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-Name Accounting Standards Codification

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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.

+ References

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

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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 Statement of Financial Accounting Standard (FAS)

-Number 159

-Paragraph 18

-Subparagraph f

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-Name Accounting Standards Codification

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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 18

-Paragraph 20

-Subparagraph a (1)

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- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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