The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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The carrying amount of capitalized computer software costs net of accumulated amortization as of the balance sheet date.

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Software and Other Intangible Assets - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Software, net	$ 144,665		$ 144,665		$ 155,386
Software, accumulated amortization	239,500		239,500		230,700
Other intangible assets amortization expense	4,800	$ 4,800	9,700	$ 9,600
Software Marketed for External Sale [Member]
Finite-Lived Intangible Assets [Line Items]
Software, net	33,800		33,800		40,900
Software, amortization expense	3,400	3,200	$ 7,000	6,500
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	110,900		$ 110,900		$ 114,500
Software, amortization expense	$ 10,300	$ 11,300	$ 20,800	$ 22,600
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