Goodwill and Other Intangible Assets - Weighted-Average Amortization Period by Major Class (Detail)	3 Months Ended
	Mar. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Weighted-average amortization period (in years)	11 years
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Weighted-average amortization period (in years)	15 years
Developed technology
Finite-Lived Intangible Assets [Line Items]
Weighted-average amortization period (in years)	3 years
Internally developed software
Finite-Lived Intangible Assets [Line Items]
Weighted-average amortization period (in years)	4 years
Patents
Finite-Lived Intangible Assets [Line Items]
Weighted-average amortization period (in years)	8 years
Trademarks
Finite-Lived Intangible Assets [Line Items]
Weighted-average amortization period (in years)	6 years
Other
Finite-Lived Intangible Assets [Line Items]
Weighted-average amortization period (in years)	39 years