SEGMENT AND GEOGRAPHIC DISCLOSURES - Geographic Breakdown of Revenues and Total Long-Lived Assets (Detail) - USD ($) $ in Thousands	3 Months Ended										12 Months Ended
	Dec. 31, 2018		Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017		Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018		Dec. 31, 2017		Dec. 31, 2016
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Revenues	$ 309,799		$ 290,856	$ 343,889	$ 302,385	$ 316,334		$ 285,067	$ 312,256	$ 286,554	$ 1,246,929		$ 1,200,211		$ 1,196,696
Total Long-Lived Assets	326,166	[1]				363,380	[1]				326,166	[1]	363,380	[1]	379,235
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Revenues											908,382		871,367		889,967
Total Long-Lived Assets	298,567	[1]				330,909	[1]				298,567	[1]	330,909	[1]	348,123
Canada
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Revenues											139,900		134,256		128,122
Total Long-Lived Assets	4,165	[1]				5,377	[1]				4,165	[1]	5,377	[1]	5,901
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Revenues											126,142		119,603		108,720
Total Long-Lived Assets	20,224	[1]				22,480	[1]				20,224	[1]	22,480	[1]	20,249
Other foreign countries
Revenues from External Customers and Long-Lived Assets [Line Items]
Total Revenues											72,505		74,985		69,887
Total Long-Lived Assets	$ 3,210	[1]				$ 4,614	[1]				$ 3,210	[1]	$ 4,614	[1]	$ 4,962

[1] Excludes goodwill, intangible assets not being amortized that are to be held and used, financial instruments and deferred tax assets.