Related Party Transactions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Amounts due from/to related parties
Due from joint ventures	$ 1,240	$ 1,334
Other	14,616	9,316
Related party receivables	15,856	10,650
Alliance Building Services
Related Party Transactions
Profit participation from related party	3,500	3,800	$ 3,800
Payments made for services	23,400	21,300	21,500
Entity with Stephen L Green ownership interest
Related Party Transactions
Property management fees from related party	$ 700	$ 500	$ 400