Segment Information (Financial Information) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Segment Reporting Information [Line Items]
Operating Revenues	$ 483,131	$ 523,896	$ 1,396,960	$ 1,477,644
Depreciation and Amortization	45,326	44,498	131,668	127,433
Operating Income/(Loss)	62,296	85,721	173,255	220,345
Equity in earnings/(losses) of affiliates, net of tax	(229)	607	(1,232)	595
Net Income/(Loss) From Continuing Operations	30,828	36,002	84,722	103,965
Capital Expenditures	16,839	16,583	54,278	62,368
Assets	4,139,144		4,139,144		$ 3,906,872
Operating Segments [Member] | Property Intelligence [Member]
Segment Reporting Information [Line Items]
Operating Revenues	257,987	280,620	736,530	798,741
Depreciation and Amortization	34,086	33,280	98,383	93,580
Operating Income/(Loss)	34,737	28,822	79,984	80,931
Equity in earnings/(losses) of affiliates, net of tax	(274)	872	(1,700)	1,424
Net Income/(Loss) From Continuing Operations	31,661	28,325	68,303	78,122
Capital Expenditures	11,517	12,517	35,212	38,476
Assets	2,783,263		2,783,263		2,429,167
Operating Segments [Member] | Risk Management and Work Flow [Member]
Segment Reporting Information [Line Items]
Operating Revenues	227,329	245,764	666,206	687,023
Depreciation and Amortization	6,018	6,304	18,121	20,635
Operating Income/(Loss)	52,593	76,758	158,866	196,023
Equity in earnings/(losses) of affiliates, net of tax	0	0	0	0
Net Income/(Loss) From Continuing Operations	52,584	76,749	158,838	195,991
Capital Expenditures	3,273	2,658	11,014	7,786
Assets	1,311,730		1,311,730		1,328,008
Corporate [Member]
Segment Reporting Information [Line Items]
Operating Revenues	1	2	(1)	5
Depreciation and Amortization	5,222	4,914	15,164	13,218
Operating Income/(Loss)	(25,034)	(19,859)	(65,595)	(56,609)
Equity in earnings/(losses) of affiliates, net of tax	45	(265)	468	(829)
Net Income/(Loss) From Continuing Operations	(53,417)	(69,072)	(142,419)	(170,148)
Capital Expenditures	2,049	1,408	8,052	16,106
Assets	5,658,980		5,658,980		5,575,846
Eliminations [Member]
Segment Reporting Information [Line Items]
Operating Revenues	(2,186)	(2,490)	(5,775)	(8,125)
Depreciation and Amortization	0	0	0	0
Operating Income/(Loss)	0	0	0	0
Equity in earnings/(losses) of affiliates, net of tax	0	0	0	0
Net Income/(Loss) From Continuing Operations	0	0	0	0
Capital Expenditures	0	$ 0	0	$ 0
Assets	$ (5,614,829)		$ (5,614,829)		$ (5,426,149)