Schedule II - Valuation and Qualifying Accounts and Reserves (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Allowance For Deferred Rent Receivable [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at beginning of year			$ 7,009
Deductions			7,009
Allowance For Accounts Receivables [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at beginning of year	$ 2,006	$ 2,634	4,160
Additions	420	855	1,778
Deductions	586	1,483	3,304
Balance at end of year	$ 1,840	$ 2,006	$ 2,634