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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Goodwill and Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Jul. 03, 2017
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 52,990		$ 52,990
Intangible assets, gross	30,130		30,130
Less: Accumulated amortization	(2,328)		(1,552)
Intangible assets, net	27,802		28,578
Amortization expense	11,854	$ 12,022
Acquired technology [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	13,510		13,510
Client relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	10,760		10,760
Non-competition agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	3,470		3,470
Trade name [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	2,390		$ 2,390
Archway [Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill				$ 52,990
Amortization expense	$ 776