Quarterly Financial Data (Unaudited) (Detail) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended												12 Months Ended
		Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017		Sep. 30, 2017		Jun. 30, 2017		Mar. 31, 2017		Dec. 31, 2018	Dec. 31, 2017		Dec. 31, 2016
Revenues:
Total revenues		$ 319,950	$ 245,525	$ 234,995	$ 209,310	$ 326,395		$ 225,735		$ 240,599		$ 231,462		$ 1,009,780	$ 1,024,191		$ 1,005,701
Operating expenses:
Cost of revenue	[1]	104,281	102,473	116,261	107,336	115,993		107,393		120,357		108,543		430,351	452,286		444,914
Research and development		32,969	36,008	37,862	36,791	30,732		33,935		34,969		37,285		143,630	136,921		169,900
Selling and marketing		24,576	28,252	33,160	31,893	26,695		25,236		28,817		27,137		117,881	107,885		118,082
General and administrative		20,399	29,537	28,837	28,649	22,700	[2]	25,302	[2]	72,527	[2]	32,503	[2]	107,422	153,032	[2]	113,617
Depreciation and amortization		21,311	20,896	21,033	21,345	22,238		22,446		22,372		22,371		84,585	89,427		89,521
Total operating expenses		203,536	217,166	237,153	226,014	218,358		214,312		279,042		227,839		883,869	939,551
Operating income (loss)		116,414	28,359	(2,158)	(16,704)	108,037		11,423		(38,443)		3,623		125,911	84,640		221,130
Other income (expense):
Interest expense		(9,875)	(12,573)	(9,717)	(9,365)	(8,815)		(9,374)		(10,664)		(10,160)		(41,530)	(39,013)		(40,184)
Interest income		2,893	2,763	2,742	2,744	143		165		150		106		11,142	564		530
Other, net		(688)	(1,304)	(1,677)	(55)	(443)		(1,059)		(1,766)		649		(3,724)	(2,619)		4,105
Total other income (expense)		(7,670)	(11,114)	(8,652)	(6,676)	(9,115)		(10,268)		(12,280)		(9,405)		(34,112)	(41,068)		(35,549)
Income (loss) before income taxes		108,744	17,245	(10,810)	(23,380)	98,922		1,155		(50,723)		(5,782)		91,799	43,572		185,581
Income tax expense (benefit)		21,054	2,012	3,764	(3,952)	65,758		(2,233)		(20,914)		(4,174)		22,878	38,437		56,046
Net income (loss)		$ 87,690	$ 15,233	$ (14,574)	$ (19,428)	$ 33,164		$ 3,388		$ (29,809)		$ (1,608)		$ 68,921	$ 5,135		$ 129,535
Earnings (loss) per share
Basic		$ 0.76	$ 0.13	$ (0.13)	$ (0.17)	$ 0.28		$ 0.03		$ (0.25)		$ (0.01)		$ 0.59	$ 0.04		$ 1.10
Diluted		$ 0.74	$ 0.13	$ (0.13)	$ (0.17)	$ 0.28		$ 0.03		$ (0.25)		$ (0.01)		$ 0.59	$ 0.04		$ 1.09
Software as a service and platform as a service [Member]
Revenues:
Total revenues		$ 110,626	$ 104,519	$ 113,600	$ 104,280	$ 112,895		$ 99,761		$ 113,469		$ 99,447		$ 433,025	$ 425,572		$ 411,289
License [Member]
Revenues:
Total revenues		137,991	68,964	45,555	28,046	129,546		50,017		54,180		59,381		280,556	293,124		273,466
Maintenance [Member]
Revenues:
Total revenues		53,065	54,373	55,048	56,659	55,242		56,349		56,009		54,471		219,145	222,071		233,476
Services [Member]
Revenues:
Total revenues		$ 18,268	$ 17,669	$ 20,792	$ 20,325	$ 28,712		$ 19,608		$ 16,941		$ 18,163		$ 77,054	$ 83,424		$ 87,470

[1] The cost of revenue excludes charges for depreciation but includes amortization of purchased and developed software for resale.

[2] General and administrative expenses in the second quarter includes the BHMI judgment.