Software and Other Intangible Assets - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Software, net	$ 150,653		$ 155,386
Software, accumulated amortization	236,800		230,700
Other intangible assets amortization expense	4,900	$ 4,800
Software Marketed for External Sale [Member]
Finite-Lived Intangible Assets [Line Items]
Software, net	37,900		40,900
Software, amortization expense	$ 3,600	3,300
Software Marketed for External Sale [Member] | Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful life	3 years
Software Marketed for External Sale [Member] | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful life	10 years
Software Acquired or Developed for Internal Use [Member]
Finite-Lived Intangible Assets [Line Items]
Software, net	$ 112,800		$ 114,500
Software, amortization expense	$ 10,500	$ 11,300
Software Acquired or Developed for Internal Use [Member] | Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful life	3 years
Software Acquired or Developed for Internal Use [Member] | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful life	10 years