Components of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deferred Income Tax Assets And Liabilities [Line Items]
Asset reserves and liabilities not yet deductible for tax	$ 28,589	$ 31,634
Tax over book basis of certain assets	893	924
Net operating loss and tax credit carryforwards	5,287	5,008
Intangible contract value	2,717	2,877
Noncurrent deferred tax assets, Other	460	579
Total noncurrent deferred tax assets	37,946	41,022
Less valuation allowance	(3,780)	(4,065)
Total noncurrent deferred tax assets	34,166	36,957
Book over tax basis of certain assets	(15,238)	(11,332)
Intangible lease value	(8,862)	(9,431)
Deferred tax liabilities, other	(242)	(664)
Total noncurrent deferred tax liabilities	(24,342)	(21,427)
Non-current deferred tax assets	$ 9,824	$ 15,530