Operating Revenues - Operating Revenues by Solution Type (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2018
Disaggregation of Revenue [Line Items]
Operating Revenue	$ 488,401	$ 933,301
Property insights
Disaggregation of Revenue [Line Items]
Operating Revenue	127,293	250,965
Insurance & spatial solutions
Disaggregation of Revenue [Line Items]
Operating Revenue	40,861	78,025
Flood data services
Disaggregation of Revenue [Line Items]
Operating Revenue	18,911	35,885
Valuations solutions
Disaggregation of Revenue [Line Items]
Operating Revenue	81,456	152,900
Credit solutions
Disaggregation of Revenue [Line Items]
Operating Revenue	78,883	160,368
Property tax solutions
Disaggregation of Revenue [Line Items]
Operating Revenue	117,480	$ 207,361
Expected service period revenue is recognized		10 years
Other
Disaggregation of Revenue [Line Items]
Operating Revenue	23,517	$ 47,797
Operating Segments | PIRM
Disaggregation of Revenue [Line Items]
Operating Revenue	182,655	356,422
Operating Segments | PIRM | Property insights
Disaggregation of Revenue [Line Items]
Operating Revenue	127,293	250,965
Operating Segments | PIRM | Insurance & spatial solutions
Disaggregation of Revenue [Line Items]
Operating Revenue	40,861	78,025
Operating Segments | PIRM | Flood data services
Disaggregation of Revenue [Line Items]
Operating Revenue	0	0
Operating Segments | PIRM | Valuations solutions
Disaggregation of Revenue [Line Items]
Operating Revenue	0	0
Operating Segments | PIRM | Credit solutions
Disaggregation of Revenue [Line Items]
Operating Revenue	0	0
Operating Segments | PIRM | Property tax solutions
Disaggregation of Revenue [Line Items]
Operating Revenue	0	0
Operating Segments | PIRM | Other
Disaggregation of Revenue [Line Items]
Operating Revenue	14,501	27,432
Operating Segments | UWS
Disaggregation of Revenue [Line Items]
Operating Revenue	308,226	581,645
Operating Segments | UWS | Property insights
Disaggregation of Revenue [Line Items]
Operating Revenue	0	0
Operating Segments | UWS | Insurance & spatial solutions
Disaggregation of Revenue [Line Items]
Operating Revenue	0	0
Operating Segments | UWS | Flood data services
Disaggregation of Revenue [Line Items]
Operating Revenue	18,911	35,885
Operating Segments | UWS | Valuations solutions
Disaggregation of Revenue [Line Items]
Operating Revenue	81,456	152,900
Operating Segments | UWS | Credit solutions
Disaggregation of Revenue [Line Items]
Operating Revenue	78,883	160,368
Operating Segments | UWS | Property tax solutions
Disaggregation of Revenue [Line Items]
Operating Revenue	117,480	207,361
Operating Segments | UWS | Other
Disaggregation of Revenue [Line Items]
Operating Revenue	11,496	25,131
Corporate and Eliminations
Disaggregation of Revenue [Line Items]
Operating Revenue	(2,480)	(4,766)
Corporate and Eliminations | Property insights
Disaggregation of Revenue [Line Items]
Operating Revenue	0	0
Corporate and Eliminations | Insurance & spatial solutions
Disaggregation of Revenue [Line Items]
Operating Revenue	0	0
Corporate and Eliminations | Flood data services
Disaggregation of Revenue [Line Items]
Operating Revenue	0	0
Corporate and Eliminations | Valuations solutions
Disaggregation of Revenue [Line Items]
Operating Revenue	0	0
Corporate and Eliminations | Credit solutions
Disaggregation of Revenue [Line Items]
Operating Revenue	0	0
Corporate and Eliminations | Property tax solutions
Disaggregation of Revenue [Line Items]
Operating Revenue	0	0
Corporate and Eliminations | Other
Disaggregation of Revenue [Line Items]
Operating Revenue	$ (2,480)	$ (4,766)