Goodwill and Other Intangible Assets, Net - Components of Other Intangible Assets (Detail) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2018	Dec. 31, 2017
Schedule Of Acquired Finite And Indefinite Lived Intangible Asset By Major Class [Line Items]
Total gross definite life intangible assets	$ 295,172	$ 292,525
Accumulated Amortization	88,933	73,481
Net definite life intangible assets	$ 206,239	$ 219,044
Weighted-Average Remaining Life	11 years 6 months	11 years 10 months 24 days
Total indefinite life intangible assets	$ 91,870	$ 91,977
Total definite and indefinite life intangible assets, gross, excluding goodwill	387,042	384,502
Total definite and indefinite life intangible assets, net, excluding goodwill	298,109	311,021
Trade Names [Member]
Schedule Of Acquired Finite And Indefinite Lived Intangible Asset By Major Class [Line Items]
Total indefinite life intangible assets	83,941	84,048
Licenses [Member]
Schedule Of Acquired Finite And Indefinite Lived Intangible Asset By Major Class [Line Items]
Total indefinite life intangible assets	7,929	7,929
Customer-Related Intangible Assets [Member]
Schedule Of Acquired Finite And Indefinite Lived Intangible Asset By Major Class [Line Items]
Total gross definite life intangible assets	205,343	203,743
Accumulated Amortization	36,494	27,820
Net definite life intangible assets	$ 168,849	$ 175,923
Weighted-Average Remaining Life	13 years 1 month 6 days	13 years 8 months 12 days
Technology [Member]
Schedule Of Acquired Finite And Indefinite Lived Intangible Asset By Major Class [Line Items]
Total gross definite life intangible assets	$ 24,024	$ 24,025
Accumulated Amortization	11,466	9,741
Net definite life intangible assets	$ 12,558	$ 14,284
Weighted-Average Remaining Life	3 years 8 months 12 days	4 years 2 months 12 days
Noncompete Agreements [Member]
Schedule Of Acquired Finite And Indefinite Lived Intangible Asset By Major Class [Line Items]
Total gross definite life intangible assets	$ 35,704	$ 34,333
Accumulated Amortization	19,918	16,180
Net definite life intangible assets	$ 15,786	$ 18,153
Weighted-Average Remaining Life	2 years 7 months 6 days	2 years 8 months 12 days
Patents [Member]
Schedule Of Acquired Finite And Indefinite Lived Intangible Asset By Major Class [Line Items]
Total gross definite life intangible assets	$ 10,412	$ 10,629
Accumulated Amortization	10,179	10,049
Net definite life intangible assets	$ 233	$ 580
Weighted-Average Remaining Life	6 years 1 month 6 days	3 years 7 months 6 days
All Other [Member]
Schedule Of Acquired Finite And Indefinite Lived Intangible Asset By Major Class [Line Items]
Total gross definite life intangible assets	$ 19,689	$ 19,795
Accumulated Amortization	10,876	9,691
Net definite life intangible assets	$ 8,813	$ 10,104
Weighted-Average Remaining Life	8 years 6 months	9 years 2 months 12 days