Estimated Useful Lives (Detail)	3 Months Ended
	Mar. 31, 2018
Minimum | Developed Software and Core Technologies
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	3 years
Minimum | Customer Lists and Contract Backlog
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	5 years
Minimum | Trade Names
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	2 years
Maximum | Developed Software and Core Technologies
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	11 years
Maximum | Customer Lists and Contract Backlog
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	15 years
Maximum | Trade Names
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	10 years