Amount of amortization of lease incentive costs incurred by the lessor for the benefit of the lessee.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 25

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=7501430&loc=d3e40010-112707

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 25

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=7501430&loc=d3e40019-112707

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

- Definition

This element represents the total of the costs related to real estate revenues, including management, leasing, and development services.

+ References

+ Details

Name:	us-gaap_CostOfRealEstateRevenue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The aggregate revenue from real estate operations during the reporting period.

+ 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 210.5-03.1(e))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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Balance Type:	debit
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- Definition

Difference between actual rental income due and rental income recognized on a straight-line basis.

+ References

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Data Type:	xbrli:monetaryItemType
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Segments - Additional Information (Detail) (USD $)	3 Months Ended								12 Months Ended
Segments - Additional Information (Detail) (USD $)	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
General contracting and real estate services revenues	$ 32,060,000us-gaap_RealEstateRevenueNet	$ 31,532,000us-gaap_RealEstateRevenueNet	$ 20,495,000us-gaap_RealEstateRevenueNet	$ 19,234,000us-gaap_RealEstateRevenueNet	$ 19,373,000us-gaap_RealEstateRevenueNet	$ 21,896,000us-gaap_RealEstateRevenueNet	$ 23,291,000us-gaap_RealEstateRevenueNet	$ 17,956,000us-gaap_RealEstateRevenueNet	$ 103,321,000us-gaap_RealEstateRevenueNet	$ 82,516,000us-gaap_RealEstateRevenueNet	$ 54,046,000us-gaap_RealEstateRevenueNet
General contracting and real estate services expenses									98,754,000us-gaap_CostOfRealEstateRevenue	78,813,000us-gaap_CostOfRealEstateRevenue	50,103,000us-gaap_CostOfRealEstateRevenue
Non-cash stock compensation									917,000us-gaap_ShareBasedCompensation	1,249,000us-gaap_ShareBasedCompensation
Accrued straight-line rental revenue									2,203,000us-gaap_StraightLineRent	1,055,000us-gaap_StraightLineRent	2,158,000us-gaap_StraightLineRent
Amortization of leasing incentive									(700,000)us-gaap_AmortizationOfLeaseIncentives	(800,000)us-gaap_AmortizationOfLeaseIncentives	(800,000)us-gaap_AmortizationOfLeaseIncentives
General and Administrative Expenses [Member]
Segment Reporting Information [Line Items]
Non-cash stock compensation									700,000	1,200,000
General Contracting and Real Estate Services [Member]
Segment Reporting Information [Line Items]
General contracting and real estate services revenues									103,321,000	82,516,000	54,046,000
General contracting and real estate services expenses									98,754,000	78,813,000	50,103,000
Non-cash stock compensation									200,000
General Contracting and Real Estate Services [Member] \| Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
General contracting and real estate services revenues									85,400,000	35,700,000	1,400,000
General contracting and real estate services expenses									$ 84,600,000	$ 35,400,000	$ 1,300,000