Segment Information - Selected Financial Data (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Segment Reporting Information [Line Items]
Revenue	$ 291,485	$ 205,855
Depreciation and amortization	(33,822)	(24,852)
Stock-based compensation expense	(6,950)	(6,585)
Corporate and unallocated expenses	(24,541)	(24,662)
Interest, net	(14,271)	(8,581)
Other, net	(9,758)	(1,912)
Loss before income taxes	(35,312)	(38,586)
Operating Segments \| ACI On Demand
Segment Reporting Information [Line Items]
Revenue	192,950	109,848
Segment Adjusted EBITDA	23,121	(262)
Depreciation and amortization	(9,332)	(7,562)
Stock-based compensation expense	(2,026)	(1,951)
Operating Segments \| ACI On Premise
Segment Reporting Information [Line Items]
Revenue	98,535	96,007
Segment Adjusted EBITDA	30,909	28,268
Depreciation and amortization	(3,106)	(3,030)
Stock-based compensation expense	(2,030)	(1,956)
Corporate and Other
Segment Reporting Information [Line Items]
Depreciation and amortization	(21,384)	(14,260)
Stock-based compensation expense	$ (2,894)	$ (2,678)

Other operating expenses related to corporate functions and not allocated to reportable segments.

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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The net amount of operating interest income (expense).

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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