Investment in Unconsolidated Ventures - Summarized Income Statement Information additional information (Detail) (USD $)	3 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Deferred Gain on Sale	$ 1,587,000
Unrecognized basis difference on equity method investment	1,373,000
Equity Method Investments [Member]
Schedule of Equity Method Investments [Line Items]
Long-term Debt, Current Maturities	78,947,000	65,795,000
Equity Method Investments [Member] \| Non-recourse Debt [Member]
Schedule of Equity Method Investments [Line Items]
Long-term Debt, Current Maturities	$ 51,788,000	$ 42,566,000

This element represents disclosure of the amount of gain which has been deferred as the result of the sale of a business or operating assets to a highly leveraged entity which deferred gain has been reflected in the accompanying statement of financial position as reduction from the related asset.

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section U

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 40

-Section S99

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6955272&loc=d3e221323-122791

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- Definition

Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee.

+ 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)(3)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

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- Definition

Amount of long-term debt, after unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19,20)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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