Segment Financial Information (Table) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Statement [Abstract]
Operating revenue	$ 390,886	$ 386,439	$ 386,013	$ 364,772	$ 345,512	$ 367,454	$ 365,970	$ 326,104	$ 1,528,110	$ 1,405,040	$ 1,404,401
Depreciation and amortization									146,607	138,394	126,332
Operating income/(loss)	27,032	65,920	60,707	49,265	36,161	77,752	41,020	14,825	202,924	169,758	142,142
Equity in earnings/(loss) of affiliates, net of tax	1,789	$ 3,498	$ 4,667	$ 3,766	3,832	$ 4,031	$ 3,875	$ 2,382	13,720	14,120	27,361
Net income/(loss) from continuing operations									129,552	91,008	100,260
Capital expenditures									80,558	87,154	106,586
Statement of Financial Position [Abstract]
Investment in affiliates, net	69,205				103,598				69,205	103,598
Long-lived assets	3,158,784				3,015,737				3,158,784	3,015,737
Total assets	3,701,050				3,516,362				3,701,050	3,516,362
Segment Reporting Information, Assets (Excluding Discontinued Operations Assets)	3,700,369				3,512,095				3,700,369	3,512,095
Domestic Country [Member]
Income Statement [Abstract]
Operating revenue									1,397,394	1,263,950	1,302,483
Statement of Financial Position [Abstract]
Long-lived assets	2,838,494				2,705,307				2,838,494	2,705,307
Foreign Country [Member]
Income Statement [Abstract]
Operating revenue									130,716	141,090	101,918
Statement of Financial Position [Abstract]
Long-lived assets	320,290				310,430				320,290	310,430
Property Intelligence [Member]
Income Statement [Abstract]
Operating revenue									663,344	598,113	518,622
Depreciation and amortization									96,766	92,615	68,375
Operating income/(loss)									72,761	70,181	56,515
Equity in earnings/(loss) of affiliates, net of tax									22,622	22,949	43,269
Net income/(loss) from continuing operations									94,522	100,070	106,842
Capital expenditures									48,902	48,535	46,726
Statement of Financial Position [Abstract]
Investment in affiliates, net	61,765				96,356				61,765	96,356
Long-lived assets	1,856,410				1,693,332				1,856,410	1,693,332
Total assets	2,058,412				1,838,423				2,058,412	1,838,423
Property Intelligence [Member] | Domestic Country [Member]
Income Statement [Abstract]
Operating revenue									535,405	460,370	422,501
Statement of Financial Position [Abstract]
Long-lived assets	1,536,133				1,382,922				1,536,133	1,382,922
Property Intelligence [Member] | Foreign Country [Member]
Income Statement [Abstract]
Operating revenue									127,939	137,743	96,121
Statement of Financial Position [Abstract]
Long-lived assets	320,277				310,410				320,277	310,410
Risk Management and Work Flow [Member]
Income Statement [Abstract]
Operating revenue									875,057	816,717	895,953
Depreciation and amortization									33,723	31,717	36,591
Operating income/(loss)									216,178	166,640	181,673
Equity in earnings/(loss) of affiliates, net of tax									0	0	0
Net income/(loss) from continuing operations									216,147	166,631	182,923
Capital expenditures									12,714	16,184	27,407
Statement of Financial Position [Abstract]
Investment in affiliates, net	0				0				0	0
Long-lived assets	1,183,318				1,208,256				1,183,318	1,208,256
Total assets	1,316,785				1,345,958				1,316,785	1,345,958
Risk Management and Work Flow [Member] | Domestic Country [Member]
Income Statement [Abstract]
Operating revenue									872,319	813,401	890,787
Statement of Financial Position [Abstract]
Long-lived assets	1,183,305				1,208,236				1,183,305	1,208,236
Risk Management and Work Flow [Member] | Foreign Country [Member]
Income Statement [Abstract]
Operating revenue									2,738	3,316	5,166
Statement of Financial Position [Abstract]
Long-lived assets	13				20				13	20
Corporate Segment [Member]
Income Statement [Abstract]
Operating revenue									39	31	631
Depreciation and amortization									16,118	14,062	21,366
Operating income/(loss)									(86,015)	(67,063)	(96,046)
Equity in earnings/(loss) of affiliates, net of tax									(8,902)	(8,829)	(15,908)
Net income/(loss) from continuing operations									(181,117)	(163,728)	(189,505)
Capital expenditures									18,942	22,435	32,453
Statement of Financial Position [Abstract]
Investment in affiliates, net	7,440				7,242				7,440	7,242
Long-lived assets	5,139,576				4,888,730				5,139,576	4,888,730
Total assets	5,346,324				5,102,328				5,346,324	5,102,328
Corporate Segment [Member] | Domestic Country [Member]
Income Statement [Abstract]
Operating revenue									0	0	0
Statement of Financial Position [Abstract]
Long-lived assets	4,393,637				4,142,791				4,393,637	4,142,791
Corporate Segment [Member] | Foreign Country [Member]
Income Statement [Abstract]
Operating revenue									39	31	631
Statement of Financial Position [Abstract]
Long-lived assets	745,939				745,939				745,939	745,939
Eliminations [Member]
Income Statement [Abstract]
Operating revenue									(10,330)	(9,821)	(10,805)
Depreciation and amortization									0	0	0
Operating income/(loss)									0	0	0
Equity in earnings/(loss) of affiliates, net of tax									0	0	0
Net income/(loss) from continuing operations									0	(11,965)	0
Capital expenditures									0	0	0
Statement of Financial Position [Abstract]
Investment in affiliates, net	0				0				0	0
Long-lived assets	(5,020,520)				(4,774,581)				(5,020,520)	(4,774,581)
Total assets	(5,021,152)				(4,774,614)				(5,021,152)	(4,774,614)
Eliminations [Member] | Domestic Country [Member]
Income Statement [Abstract]
Operating revenue									(10,330)	(9,821)	(10,805)
Statement of Financial Position [Abstract]
Long-lived assets	(4,274,581)				(4,028,642)				(4,274,581)	(4,028,642)
Eliminations [Member] | Foreign Country [Member]
Income Statement [Abstract]
Operating revenue									0	0	$ 0
Statement of Financial Position [Abstract]
Long-lived assets	$ (745,939)				$ (745,939)				$ (745,939)	$ (745,939)