General - Schedule of Real Estate Held for Sale (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Real Estate Held For Sale [Line Items]
Accumulated depreciation and amortization	$ (100,284)	$ (99,510)
Real estate held for sale, net	2,930us-gaap_RealEstateHeldforsale	4,343us-gaap_RealEstateHeldforsale
Real Estate Held for Sale [Member]
Real Estate Held For Sale [Line Items]
Land	1,650	2,383
Buildings and improvements	1,901	3,140
Real estate held for sale, gross	3,551	5,523
Accumulated depreciation and amortization	(621)	(1,180)
Real estate held for sale, net	$ 2,930	$ 4,343

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Aggregate of the carrying amounts as of the balance sheet date of investments in building and building improvements.

+ References

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- Definition

Carrying value of land held for sale.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.(a),1(d))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 45

-Paragraph 14

-URI http://asc.fasb.org/extlink&oid=8077374&loc=d3e2599-110228

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Subparagraph d

-Article 7

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Carrying amount as of the balance sheet date of investments in land and buildings held for sale, excluding real estate considered to be inventory of the entity.

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- Definition

The cumulative amount of depreciation for real estate property held for investment purposes.

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Amount of real estate investment property which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

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