Regulatory Investigation - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 1993 Partnership
Regulatory Investigation [Abstract]
Number of partnership relating to regulatory investigation		3
Estimated an aggregate recovery	$ 5,918,000	$ 3,000,000
Affiliates reflecting estimated receivable	3,000,000	3,000,000
Recovery of amounts previously written off	$ 1,229,000

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(4)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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- Definition

The cash inflow from earnings received from real estate partnerships.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

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- Definition

Affiliates reflecting estimated receivable.

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- Definition

Number of partnerships related to regulatory investigation of former general partners.

+ References

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