Discontinued Operations and Assets Held For Sale - Schedule of Real Estate Held for Sale (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Real Estate Held For Sale [Line Items]
Less accumulated depreciation and amortization	$ (133,353)	$ (120,576)
Real estate, net	$ 837,611	661,590
Real Estate Held for Sale [Member]
Real Estate Held For Sale [Line Items]
Land		117
Buildings and improvements		528
Real estate held for sale, gross		645
Real estate, net		$ 645

Real Estate Held For Sale [Line Items]

No definition available.

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- Definition

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

+ References

+ Details

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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=68055307&loc=d3e2599-110228

+ Details

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- Definition

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

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- Definition

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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- Definition

Amount of real estate investment property, net of accumulated depreciation, 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.

+ References

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