Deferred Revenue and Performance Obligations - Deferred Revenue (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2020 USD ($)
Disaggregation of Revenue
Deferred revenue	$ 366,126
Contract With Customer Liability
Balance as of December 31, 2019	412,694
Deferral of revenue	198,324
Recognition of deferred revenue	(244,892)
Balance as of March 31, 2020	366,126
Operating segments | Enterprise Software
Disaggregation of Revenue
Deferred revenue	375,838
Contract With Customer Liability
Balance as of December 31, 2019	375,838
Balance as of March 31, 2020	333,314
Operating segments | Appraisal and Tax
Disaggregation of Revenue
Deferred revenue	35,487
Contract With Customer Liability
Balance as of December 31, 2019	35,487
Balance as of March 31, 2020	31,205
Corporate
Disaggregation of Revenue
Deferred revenue	1,369
Contract With Customer Liability
Balance as of December 31, 2019	1,369
Balance as of March 31, 2020	$ 1,607