Goodwill and Other Intangible Assets (Details) (USD $) In Thousands	6 Months Ended			6 Months Ended
Jun. 30, 2011	Jun. 30, 2011 US Operating Segment [Member]	Dec. 31, 2010 US Operating Segment [Member]	Jun. 30, 2011 International Operating Segment [Member]
Summery of goodwill
Balance at December 31, 2010	$ 1,122,971	$ 948,026	$ 948,026	$ 174,945
Foreign currency translation adjustments	8,032			8,032
Balance at June 30, 2011	$ 1,131,003	$ 948,026	$ 948,026	$ 182,977

Carrying amount as of the balance sheet date, which is the cumulative amount paid, adjusted for any amortization recognized prior to adoption of FAS 142 and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Paragraph 43

+ Details

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Balance Type:	debit
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ Details

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- Definition

Reflects net changes to the recorded value of goodwill for foreign currency translation adjustments and purchase accounting adjustments needed to revise the carrying amount of goodwill to fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142

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