Selected Segment Financial Data, Revenues and Operating Income (Loss) (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Segment Reporting Information [Line Items]
Revenues	$ 209,310	$ 231,462
Stock-based compensation	(6,362)	(6,297)
Corporate and unallocated expenses	(20,014)	(25,830)
Interest, net	(6,621)	(10,054)
Other, net	(55)	649
Loss before income taxes	(23,380)	(5,782)
Depreciation and amortization expense	24,993	25,638
ACI On Premise [Member]
Segment Reporting Information [Line Items]
Revenues	105,030	131,908
ACI On Demand [Member]
Segment Reporting Information [Line Items]
Revenues	104,280	99,554
Operating Segments [Member] | ACI On Premise [Member]
Segment Reporting Information [Line Items]
Revenues	105,030	131,908
Segment Adjusted EBITDA	38,898	68,395
Depreciation and amortization expense	2,975	3,261
Operating Segments [Member] | ACI On Demand [Member]
Segment Reporting Information [Line Items]
Revenues	104,280	99,554
Segment Adjusted EBITDA	(4,233)	(7,007)
Depreciation and amortization expense	7,736	8,388
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization expense	$ 14,282	$ 13,989