Segment and Related Information - Schedule of Segment Revenues and Operations (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Software licenses and royalties									$ 74,306	$ 59,008	$ 49,065
Subscriptions									142,704	111,933	87,848
Software services									174,804	139,852	113,821
Maintenance									322,969	245,537	212,696
Appraisal services									26,287	25,065	21,802
Hardware and other									14,973	9,627	7,869
Intercompany											0
Total revenues	$ 193,281	$ 194,497	$ 188,972	$ 179,293	$ 158,916	$ 150,845	$ 146,295	$ 134,966	756,043	591,022	493,101
Depreciation and amortization expense									50,301	19,574	14,605
Segment operating income									167,271	118,388	101,226
Capital expenditures									36,723	13,504	9,449
Segment assets	1,357,945				1,356,570				1,357,945	1,356,570	569,812
Operating segments | Enterprise Software Solutions
Segment Reporting Information [Line Items]
Software licenses and royalties									68,844	54,376	46,047
Subscriptions									135,516	107,090	84,322
Software services									158,478	129,068	104,146
Maintenance									304,380	227,586	195,881
Appraisal services											0
Hardware and other									11,942	6,935	5,398
Intercompany									6,742	4,025	2,812
Total revenues									685,902	529,080	438,606
Depreciation and amortization expense									43,962	15,413	11,140
Segment operating income									190,817	141,401	114,993
Capital expenditures									23,843	6,112	3,644
Segment assets	295,260				265,877				295,260	265,877	170,369
Operating segments | Appraisal and Tax Software Solutions and Services
Segment Reporting Information [Line Items]
Software licenses and royalties									5,462	4,632	3,018
Subscriptions									7,188	4,843	3,526
Software services									16,326	10,784	9,675
Maintenance									18,589	17,951	16,815
Appraisal services									26,287	25,065	21,802
Hardware and other									16	12	11
Intercompany											0
Total revenues									73,868	63,287	54,847
Depreciation and amortization expense									984	867	866
Segment operating income									18,286	15,477	11,603
Capital expenditures									1,432	646	359
Segment assets	31,769				22,283				31,769	22,283	16,463
Corporate
Segment Reporting Information [Line Items]
Software licenses and royalties											0
Subscriptions											0
Software services											0
Maintenance											0
Appraisal services											0
Hardware and other									3,015	2,680	2,460
Intercompany									(6,742)	(4,025)	(2,812)
Total revenues									(3,727)	(1,345)	(352)
Depreciation and amortization expense									5,355	3,294	2,599
Segment operating income									(41,832)	(38,490)	(25,370)
Capital expenditures									11,448	6,746	5,446
Segment assets	$ 1,030,916				$ 1,068,410				$ 1,030,916	$ 1,068,410	$ 382,980