Income Taxes - Schedule of Deferred Tax Assets and liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Property and equipment	$ (4,336)	$ (3,781)
Unbilled rent	(8,953)	(7,045)
Partnership investments	(2,099)	(5,103)
Other	(6,702)	(6,757)
Total deferred tax liabilities	(22,090)	(22,686)
Operating loss and interest deduction carry forwards	24,580	28,289
Other	8,726	10,085
Total deferred tax assets	33,306	38,374
Valuation allowance	(11,101)	(15,975)
Total net deferred tax assets	22,205	22,399
Net deferred tax asset	$ 115
Net deferred tax liability		$ (287)