Basis of Presentation and Significant Accounting Policies - Additional Information (Details) - USD ($)		3 Months Ended
	Jan. 01, 2018	Mar. 31, 2018	Mar. 31, 2017
Property Plant And Equipment [Line Items]
Increase in cash provided by used in operating activities continuing operations		$ 35,569,000	$ 40,716,000
Decrease in cash provided by used in investing activities continuing operations		$ (53,345,000)	(40,714,000)
ASU 2016-18 [Member]
Property Plant And Equipment [Line Items]
Increase in cash provided by used in operating activities continuing operations			23,000,000
Decrease in cash provided by used in investing activities continuing operations			$ (22,824,000)
ASU 2017-05 [Member] | RDF [Member] | 75 Howard [Member]
Property Plant And Equipment [Line Items]
Adjustment to investments in unconsolidated joint ventures	$ 7,086,000