Segments - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended	9 Months Ended	0 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013 Tenants	Sep. 30, 2014 General and Administrative Expenses [Member]	Sep. 30, 2013 General and Administrative Expenses [Member]	Sep. 30, 2014 General and Administrative Expenses [Member]	Sep. 30, 2013 General and Administrative Expenses [Member]	Sep. 30, 2014 Dimmock Square [Member]	Sep. 30, 2014 Dimmock Square [Member]	Jan. 17, 2014 Bermuda Crossroads and Smith's Landing [Member]	May 13, 2013 Bermuda Crossroads and Smith's Landing [Member]	Sep. 30, 2014 General Contracting and Real Estate Services [Member]	Sep. 30, 2013 General Contracting and Real Estate Services [Member]	Sep. 30, 2014 General Contracting and Real Estate Services [Member]	Sep. 30, 2013 General Contracting and Real Estate Services [Member]	Sep. 30, 2014 General Contracting and Real Estate Services [Member] Intersegment Eliminations [Member]	Sep. 30, 2013 General Contracting and Real Estate Services [Member] Intersegment Eliminations [Member]	Sep. 30, 2014 General Contracting and Real Estate Services [Member] Intersegment Eliminations [Member]	Sep. 30, 2013 General Contracting and Real Estate Services [Member] Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
General contracting and real estate services revenues	$ 31,532,000	$ 21,896,000	$ 71,261,000	$ 63,143,000									$ 31,532,000	$ 21,896,000	$ 71,261,000	$ 63,143,000	$ (24,200,000)	$ (13,300,000)	$ (68,800,000)	$ (18,900,000)
General contracting and real estate services expenses	30,468,000	20,907,000	67,807,000	60,868,000									30,468,000	20,907,000	67,807,000	60,868,000	(24,100,000)	(13,100,000)	(68,200,000)	(18,700,000)
Non-cash stock compensation			720,000	1,012,000	200,000	200,000	500,000	1,000,000					100,000		200,000
Acquisition, development and other pursuit costs	174,000		174,000						200,000	200,000
Impairment of unamortized leasing assets	15,000		15,000	533,000
Number of vacated retail tenants				2
Debt defeased		13,900,000
Loss on extinguishment of debt		(1,127,000)		(2,252,000)
Repayment of debt financed by proceeds from IPO and credit facility				150,000,000
Loss on extinguishment of debt, fees				600,000
Loss on extinguishment of debt, unamortized debt issuance costs				542,000
Percentage of Operating Partnership acquired	100.00%		100.00%									100.00%
Gain loss from remeasurement of equity method investment											$ 9,500,000