Property Expenses of Reportable Segments (Detail) (Predecessor, USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Segment Reporting Information [Line Items]
Rental expenses	$ 3,229	$ 2,864
Real estate taxes	1,212	1,183
Property expenses	4,441	4,047
Office Real Estate
Segment Reporting Information [Line Items]
Rental expenses	1,405	1,302
Real estate taxes	541	544
Retail Real Estate
Segment Reporting Information [Line Items]
Rental expenses	1,220	1,076
Real estate taxes	460	453
Mutifamily Real Estate
Segment Reporting Information [Line Items]
Rental expenses	604	482
Real estate taxes	211	186
Other
Segment Reporting Information [Line Items]
Rental expenses		$ 4

Other operating costs incurred during the reporting period and may include amounts paid to maintain the property.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.2)

-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Costs incurred and are directly related to generating revenues from leased and rented property or equipment.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.2(c))

-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

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- Definition

A tax based on the assessed value of real estate by the local government. The tax is usually based on the value of property (including the land).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 720

-SubTopic 30

-Section 45

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6419918&loc=d3e35301-107843

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 43

-Section A

-Paragraph 2, 17

-Chapter 10

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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