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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Software and Other Intangible Assets - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Software, net	$ 235,936		$ 235,936		$ 137,228
Software, accumulated amortization	288,300		288,300		252,200
Other intangible assets amortization expense	9,400	$ 4,700	22,500	$ 14,400
Software for Resale
Finite-Lived Intangible Assets [Line Items]
Software, net	18,500		18,500		27,500
Software, amortization expense	2,800	2,600	8,800	9,600
Software for Internal Use
Finite-Lived Intangible Assets [Line Items]
Software, net	217,400		217,400		$ 109,700
Software, amortization expense	$ 15,700	$ 10,200	$ 39,400	$ 31,000
Minimum \| Software for Resale
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life (in years)			3 years
Minimum \| Software for Internal Use
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life (in years)			3 years
Maximum \| Software for Resale
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life (in years)			10 years
Maximum \| Software for Internal Use
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life (in years)			10 years