Schedule II - Consolidated Valuation and Qualifying Accounts (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Allowance for doubtful accounts
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	$ 2,566	$ 2,550	$ 3,040
Charged/(Credited) to Expense	1,785	1,115	815
Other Adjustments	208	(41)	79
Deductions	(1,164)	(1,058)	(1,384)
Balance at End of Period	$ 3,395	$ 2,566	2,550
Deferred tax valuation allowance
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period			1,206
Charged/(Credited) to Expense			$ (1,206)