Equity-Method Investments - Schedule of Equity-Method Investments (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Schedule of Equity Method Investments [Line Items]
Company’s (loss) income from investments in partially owned entities	$ 252	$ (1,324)	$ 112	$ (1,351)
Investments in partially owned entities	16,289		16,289		$ 15,942
Total
Schedule of Equity Method Investments [Line Items]
Revenues	12,925	11,867	25,533	23,437
Operating (loss) income	550	(2,169)	657	(2,141)
Net (loss) income	798	(2,469)	867	(2,520)
Company’s (loss) income from investments in partially owned entities	252	(1,324)	112	(1,351)
CMAL
Schedule of Equity Method Investments [Line Items]
Revenues	9,584	8,913	19,325	18,267
Operating (loss) income	(198)	(2,886)	(175)	(3,030)
Net (loss) income	(263)	(3,000)	(265)	(3,139)
Company’s (loss) income from investments in partially owned entities	(165)	(1,527)	(286)	(1,597)
CMAH
Schedule of Equity Method Investments [Line Items]
Revenues	3,341	2,954	6,208	5,170
Operating (loss) income	748	717	832	889
Net (loss) income	1,061	531	1,132	619
Company’s (loss) income from investments in partially owned entities	417	$ 203	398	$ 246
Joint Venture
Schedule of Equity Method Investments [Line Items]
Investments in partially owned entities	$ 2,000		$ 2,000		$ 2,000