Quarterly Financial Data (Detail) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended																12 Months Ended
		Dec. 31, 2017		Sep. 30, 2017		Jun. 30, 2017		Mar. 31, 2017		Dec. 31, 2016		Sep. 30, 2016		Jun. 30, 2016		Mar. 31, 2016		Dec. 31, 2017		Dec. 31, 2016		Dec. 31, 2015
Revenues:
Software as a service and platform as a service		$ 112,895		$ 99,761		$ 113,469		$ 99,447		$ 101,119		$ 96,169		$ 102,265		$ 111,736		$ 425,572		$ 411,289		$ 446,057
License		129,546		50,017		54,180		59,381		159,277		43,256		33,510		37,423		293,124		273,466		251,205
Maintenance		55,242		56,349		56,009		54,471		58,072		57,741		60,332		57,331		222,071		233,476		241,895
Services		28,712		19,608		16,941		18,163		24,262		19,809		23,823		19,576		83,424		87,470		106,820
Total revenues		326,395		225,735		240,599		231,462		342,730		216,975		219,930		226,066		1,024,191		1,005,701		1,045,977
Operating expenses:
Cost of revenue	[1]	115,993		107,393		120,357		108,543		110,829		100,267		115,384		118,434		452,286		444,914		472,299
Research and development		30,732		33,935		34,969		37,285		37,665	[2]	42,210	[2]	46,421	[2]	43,604	[2]	136,921		169,900	[2]	145,924
Selling and marketing		26,695		25,236		28,817		27,137		29,421	[2]	29,874	[2]	28,795	[2]	29,992	[2]	107,885		118,082	[2]	129,407
General and administrative		22,700	[3]	25,302	[3]	72,527	[3]	32,503	[3]	21,639	[2]	31,390	[2]	34,520	[2]	26,068	[2]	153,032	[3]	113,617	[2]	87,419
Gain on sale of CFS assets												489				(151,952)				(151,463)
Depreciation and amortization		22,238		22,446		22,372		22,371		22,833		22,098		21,382		23,208		89,427		89,521		82,980
Total operating expenses		218,358		214,312		279,042		227,839		222,387	[2]	226,328	[2]	246,502	[2]	89,354	[2]	939,551		784,571	[2]
Operating income (loss)		108,037		11,423		(38,443)		3,623		120,343	[2]	(9,353)	[2]	(26,572)	[2]	136,712	[2]	84,640		221,130	[2]	127,948
Other income (expense):
Interest expense		(8,815)		(9,374)		(10,664)		(10,160)		(10,217)		(9,838)		(9,715)		(10,414)		(39,013)		(40,184)		(41,372)
Interest income		143		165		150		106		114		145		121		150		564		530		386
Other, net		(443)		(1,059)		(1,766)		649		(378)		2,794		2,023		(334)		(2,619)		4,105		26,411
Total other income (expense)		(9,115)		(10,268)		(12,280)		(9,405)		(10,481)		(6,899)		(7,571)		(10,598)		(41,068)		(35,549)		(14,575)
Income (loss) before income taxes		98,922		1,155		(50,723)		(5,782)		109,862	[2]	(16,252)	[2]	(34,143)	[2]	126,114	[2]	43,572		185,581	[2]	113,373
Income tax expense (benefit)		65,758		(2,233)		(20,914)		(4,174)		43,171	[2]	(6,426)	[2]	(17,669)	[2]	36,970	[2]	38,437		56,046	[2]	27,937
Net income (loss)		$ 33,164		$ 3,388		$ (29,809)		$ (1,608)		$ 66,691	[2]	$ (9,826)	[2]	$ (16,474)	[2]	$ 89,144	[2]	$ 5,135		$ 129,535	[2]	$ 85,436
Earnings (loss) per share
Basic		$ 0.28		$ 0.03		$ (0.25)		$ (0.01)		$ 0.57		$ (0.08)		$ (0.14)		$ 0.75		$ 0.04		$ 1.10		$ 0.73
Diluted		$ 0.28		$ 0.03		$ (0.25)		$ (0.01)		$ 0.56		$ (0.08)		$ (0.14)		$ 0.74		$ 0.04		$ 1.09		$ 0.72

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

[2] The Company adopted ASU 2016-09, Compensation - Stock Compensation: Improvements to Employee Share-Based Payment Accounting, ("ASU 2016-09") during the year ended December 31, 2016. The Company elected to early adopt ASU 2016-09 in the third quarter of 2016, which requires it to reflect any adjustments as of January 1, 2016, the beginning of the annual period that includes the interim period of adoption. The impact of the adoption to the Company's previously reported quarterly results for the quarters ended March 31 and June 30, 2016 are reflected in the table above.

[3] General and administrative expenses in the second quarter includes the BHMI judgment as discussed in Note 14.