Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Summary of the changes in the carrying amount of goodwill and franchise value
Goodwill, Beginning Balance	$ 800,621	$ 796,278
Goodwill, additions	107,498	17,199
Goodwill, foreign currency translation	(1,527)	(12,856)
Goodwill, Ending Balance	906,592	800,621
Franchise value, Beginning Balance	203,108	201,463
Franchise value, Additions	29,491	4,222
Franchise value, foreign currency translation	(605)	(2,577)
Franchise value, Ending Balance	$ 231,994	$ 203,108

Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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+ Details

- Definition

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.

+ References+ Details

- Definition

The increase (decrease) in 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

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+ Details