Schedule of Accrued Expenses (Detail) - USD ($) $ in Thousands		Jun. 30, 2018	Dec. 31, 2017
Schedule of Accrued Liabilities [Line Items]
Outside professional services		$ 10,143	$ 14,468
Income and other taxes		4,837	7,420
Marketing and sales program expenses		9,282	6,444
Dividends payable		2,365	2,344
Employee-related expenses		5,737	4,065
Other		12,518	10,767
Total accrued expenses	[1]	$ 44,882	$ 45,508

[1] On January 1, 2018 the Company adopted the ASC 606 revenue recognition standard and has adjusted prior periods to conform. See Note 2. "New Accounting Pronouncements" for additional information.