Guarantor Subsidiaries (Cash Flows) (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Net Cash Provided by (Used in) Operating Activities [Abstract]
Net cash (used in)/provided by operating activities - continuing operations	$ 258,789	$ 69,876
Net cash provided by operating activities - discontinued operations	9,684	(14,051)
Total cash (used in)/provided by operating activities	268,473	55,825
Net Cash Provided by (Used in) Investing Activities [Abstract]
Purchases of redeemable noncontrolling interests	0	(72,000)
Purchases of property and equipment	(38,753)	(33,558)
Purchases of capitalized data and other intangible assets	(24,054)	(19,874)
Cash paid for acquisitions, net of cash acquired	111	(214,214)
Proceeds from sale of subsidiary and other decreases in noncontrolling interest, net	10,000	22,754
Purchases of investments	0	(26,898)
Proceeds from sale of property and equipment	1,852	389
Proceeds from sale of investments	8,000	53,847
Change in restricted cash	122	2,616
Net cash used in investing activities - continuing operations	(42,722)	(286,938)
Net cash used in investing activities - discontinued operations	(1,512)	(4,380)
Total cash used in investing activities	(44,234)	(291,318)
Net Cash Provided by (Used in) Financing Activities [Abstract]
Proceeds from long-term debt	0	857,985
Debt issuance costs	0	(22,080)
Repayments of long-term debt	(114,365)	(727,699)
Share repurchased and retired	(226,629)	(176,512)
Proceeds from issuance of stock related to stock options and employee benefit plans	9,624	4,448
Minimum tax withholding paid on behalf of employees for restricted stock units	(3,015)	(2,023)
Distribution to noncontrolling interests	(10)	(4,835)
Tax benefit related to stock options	643	234
Net cash (used in)/provided by financing activities - continuing operations	(333,752)	(70,482)
Net cash provided by financing activities - discontinued operations	3	70
Total cash (used in)/provided by financing activities	(333,749)	(70,412)
Net (decrease)/increase in cash and cash equivalents	(109,510)	(305,905)
Cash and cash equivalents at beginning of period	259,266	426,212
Less: Change in cash and cash equivalents - discontinued operations	8,175	(18,361)
Cash and cash equivalents at end of period	154,552	138,668
Parent [Member]
Net Cash Provided by (Used in) Operating Activities [Abstract]
Net cash (used in)/provided by operating activities - continuing operations	(15,158)	(110,604)
Net cash provided by operating activities - discontinued operations	0	0
Total cash (used in)/provided by operating activities	(15,158)	(110,604)
Net Cash Provided by (Used in) Investing Activities [Abstract]
Purchases of redeemable noncontrolling interests		(72,000)
Purchases of property and equipment	(1,409)	(393)
Purchases of capitalized data and other intangible assets	0	0
Cash paid for acquisitions, net of cash acquired	0	(215,096)
Proceeds from sale of discontinued operations	0
Proceeds from sale of subsidiary and other decreases in noncontrolling interest, net		22,754
Purchases of investments	0	725
Proceeds from sale of property and equipment	0	0
Proceeds from sale of investments	0	0
Change in restricted cash	0	3,200
Net cash used in investing activities - continuing operations	(1,409)	(260,810)
Net cash used in investing activities - discontinued operations	0	0
Total cash used in investing activities	(1,409)	(260,810)
Net Cash Provided by (Used in) Financing Activities [Abstract]
Proceeds from long-term debt		750,000
Debt issuance costs		(21,636)
Repayments of long-term debt	(103,018)	(571,412)
Share repurchased and retired	(226,629)	(176,512)
Proceeds from issuance of stock related to stock options and employee benefit plans	9,624	4,448
Minimum tax withholding paid on behalf of employees for restricted stock units	(3,015)	(2,023)
Distribution to noncontrolling interests	0	0
Tax benefit related to stock options	643	217
Other	226,159	149,013
Net cash (used in)/provided by financing activities - continuing operations	(96,236)	132,095
Net cash provided by financing activities - discontinued operations	0	0
Total cash (used in)/provided by financing activities	(96,236)	132,095
Net (decrease)/increase in cash and cash equivalents	(112,803)	(239,319)
Cash and cash equivalents at beginning of period	229,871	355,974
Less: Change in cash and cash equivalents - discontinued operations	0	0
Plus: Cash swept from discontinued operations	12,971
Cash and cash equivalents at end of period	130,039	116,655
Guarantor Subsidiaries [Member]
Net Cash Provided by (Used in) Operating Activities [Abstract]
Net cash (used in)/provided by operating activities - continuing operations	263,740	198,806
Net cash provided by operating activities - discontinued operations	9,684	(14,051)
Total cash (used in)/provided by operating activities	273,424	184,755
Net Cash Provided by (Used in) Investing Activities [Abstract]
Purchases of redeemable noncontrolling interests		0
Purchases of property and equipment	(27,940)	(29,041)
Purchases of capitalized data and other intangible assets	(21,537)	(19,872)
Cash paid for acquisitions, net of cash acquired	111	0
Proceeds from sale of discontinued operations	10,000
Proceeds from sale of subsidiary and other decreases in noncontrolling interest, net		0
Purchases of investments	0	(27,623)
Proceeds from sale of property and equipment	1,852	389
Proceeds from sale of investments	8,000	53,847
Change in restricted cash	(185)	0
Net cash used in investing activities - continuing operations	(29,699)	(22,300)
Net cash used in investing activities - discontinued operations	(1,512)	(4,380)
Total cash used in investing activities	(31,211)	(26,680)
Net Cash Provided by (Used in) Financing Activities [Abstract]
Proceeds from long-term debt		54,375
Debt issuance costs		(444)
Repayments of long-term debt	(11,251)	(105,804)
Share repurchased and retired	0	0
Proceeds from issuance of stock related to stock options and employee benefit plans	0	0
Minimum tax withholding paid on behalf of employees for restricted stock units	0	0
Distribution to noncontrolling interests	0	(4,290)
Tax benefit related to stock options	0	17
Other	(231,582)	(141,807)
Net cash (used in)/provided by financing activities - continuing operations	(242,833)	(197,953)
Net cash provided by financing activities - discontinued operations	3	70
Total cash (used in)/provided by financing activities	(242,830)	(197,883)
Net (decrease)/increase in cash and cash equivalents	(617)	(39,808)
Cash and cash equivalents at beginning of period	9,106	23,013
Less: Change in cash and cash equivalents - discontinued operations	8,175	(18,361)
Plus: Cash swept from discontinued operations	0
Cash and cash equivalents at end of period	314	1,566
Non-Guarantor Subsidiaries [Member]
Net Cash Provided by (Used in) Operating Activities [Abstract]
Net cash (used in)/provided by operating activities - continuing operations	10,207	(18,326)
Net cash provided by operating activities - discontinued operations	0	0
Total cash (used in)/provided by operating activities	10,207	(18,326)
Net Cash Provided by (Used in) Investing Activities [Abstract]
Purchases of redeemable noncontrolling interests		0
Purchases of property and equipment	(9,404)	(4,124)
Purchases of capitalized data and other intangible assets	(2,517)	(2)
Cash paid for acquisitions, net of cash acquired	0	882
Proceeds from sale of discontinued operations	0
Proceeds from sale of subsidiary and other decreases in noncontrolling interest, net		0
Purchases of investments	0	0
Proceeds from sale of property and equipment	0	0
Proceeds from sale of investments	0	0
Change in restricted cash	307	(584)
Net cash used in investing activities - continuing operations	(11,614)	(3,828)
Net cash used in investing activities - discontinued operations	0	0
Total cash used in investing activities	(11,614)	(3,828)
Net Cash Provided by (Used in) Financing Activities [Abstract]
Proceeds from long-term debt		53,610
Debt issuance costs		0
Repayments of long-term debt	(96)	(50,483)
Share repurchased and retired	0	0
Proceeds from issuance of stock related to stock options and employee benefit plans	0	0
Minimum tax withholding paid on behalf of employees for restricted stock units	0	0
Distribution to noncontrolling interests	(10)	(545)
Tax benefit related to stock options	0	0
Other	5,423	(7,206)
Net cash (used in)/provided by financing activities - continuing operations	5,317	(4,624)
Net cash provided by financing activities - discontinued operations	0	0
Total cash (used in)/provided by financing activities	5,317	(4,624)
Net (decrease)/increase in cash and cash equivalents	3,910	(26,778)
Cash and cash equivalents at beginning of period	20,289	47,225
Less: Change in cash and cash equivalents - discontinued operations	0	0
Plus: Cash swept from discontinued operations	0
Cash and cash equivalents at end of period	24,199	20,447
Consolidation, Eliminations [Member]
Net Cash Provided by (Used in) Operating Activities [Abstract]
Net cash (used in)/provided by operating activities - continuing operations	0	0
Net cash provided by operating activities - discontinued operations	0	0
Total cash (used in)/provided by operating activities	0	0
Net Cash Provided by (Used in) Investing Activities [Abstract]
Purchases of redeemable noncontrolling interests		0
Purchases of property and equipment	0	0
Purchases of capitalized data and other intangible assets	0	0
Cash paid for acquisitions, net of cash acquired	0	0
Proceeds from sale of discontinued operations	0
Proceeds from sale of subsidiary and other decreases in noncontrolling interest, net		0
Purchases of investments	0	0
Proceeds from sale of property and equipment	0	0
Proceeds from sale of investments	0	0
Change in restricted cash	0	0
Net cash used in investing activities - continuing operations	0	0
Net cash used in investing activities - discontinued operations	0	0
Total cash used in investing activities	0	0
Net Cash Provided by (Used in) Financing Activities [Abstract]
Proceeds from long-term debt		0
Debt issuance costs		0
Repayments of long-term debt	0	0
Share repurchased and retired	0	0
Proceeds from issuance of stock related to stock options and employee benefit plans	0	0
Minimum tax withholding paid on behalf of employees for restricted stock units	0	0
Distribution to noncontrolling interests	0	0
Tax benefit related to stock options	0	0
Other	0	0
Net cash (used in)/provided by financing activities - continuing operations	0	0
Net cash provided by financing activities - discontinued operations	0	0
Total cash (used in)/provided by financing activities	0	0
Net (decrease)/increase in cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	0	0
Less: Change in cash and cash equivalents - discontinued operations	0	0
Plus: Cash swept from discontinued operations	0
Cash and cash equivalents at end of period	0	0
Total [Member]
Net Cash Provided by (Used in) Operating Activities [Abstract]
Net cash (used in)/provided by operating activities - continuing operations	258,789	69,876
Net cash provided by operating activities - discontinued operations	9,684	(14,051)
Total cash (used in)/provided by operating activities	268,473	55,825
Net Cash Provided by (Used in) Investing Activities [Abstract]
Purchases of redeemable noncontrolling interests		(72,000)
Purchases of property and equipment	(38,753)	(33,558)
Purchases of capitalized data and other intangible assets	(24,054)	(19,874)
Cash paid for acquisitions, net of cash acquired	111	(214,214)
Proceeds from sale of discontinued operations	10,000
Proceeds from sale of subsidiary and other decreases in noncontrolling interest, net		22,754
Purchases of investments	0	(26,898)
Proceeds from sale of property and equipment	1,852	389
Proceeds from sale of investments	8,000	53,847
Change in restricted cash	122	2,616
Net cash used in investing activities - continuing operations	(42,722)	(286,938)
Net cash used in investing activities - discontinued operations	(1,512)	(4,380)
Total cash used in investing activities	(44,234)	(291,318)
Net Cash Provided by (Used in) Financing Activities [Abstract]
Proceeds from long-term debt		857,985
Debt issuance costs		(22,080)
Repayments of long-term debt	(114,365)	(727,699)
Share repurchased and retired	(226,629)	(176,512)
Proceeds from issuance of stock related to stock options and employee benefit plans	9,624	4,448
Minimum tax withholding paid on behalf of employees for restricted stock units	(3,015)	(2,023)
Distribution to noncontrolling interests	(10)	(4,835)
Tax benefit related to stock options	643	234
Other	0	0
Net cash (used in)/provided by financing activities - continuing operations	(333,752)	(70,482)
Net cash provided by financing activities - discontinued operations	3	70
Total cash (used in)/provided by financing activities	(333,749)	(70,412)
Net (decrease)/increase in cash and cash equivalents	(109,510)	(305,905)
Cash and cash equivalents at beginning of period	259,266	426,212
Less: Change in cash and cash equivalents - discontinued operations	8,175	(18,361)
Plus: Cash swept from discontinued operations	12,971
Cash and cash equivalents at end of period	$ 154,552	$ 138,668