Goodwill Additional Data (Details) (USD $)	9 Months Ended		9 Months Ended	1 Months Ended	9 Months Ended	1 Months Ended
Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2011 Business and Information Services [Member] Dorado Network Systems [Member]	May 31, 2011 RP Data [Member] Data and Analytics [Member]	Sep. 30, 2011 RP Data [Member] Data and Analytics [Member]	Sep. 30, 2011 Tarasoft [Member]
Disposal Group, Including Discontinued Operation, Goodwill	$ 31,800,000	$ 155,100,000
Goodwill, Acquired During Period	$ 195,129,000		$ 18,898,000	$ 162,700,000	$ 176,231,000	$ 13,500,000
Discount Rate Used In Weighted Average Cost of Capital Calculation	12.00%
Control Premium	19.00%

The aggregate amount of goodwill acquired in the period and allocated to the reportable segment. The value is stated at fair value based on the purchase price allocation.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6905597&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 72

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

-Subparagraph e

-Clause 2

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration