Goodwill (Details 2) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2013	Sep. 30, 2013 International	Sep. 30, 2013 North America	Dec. 31, 2012 North America
Changes in the carrying amount of goodwill
Balance at the beginning of the period	$ 276,599	$ 142,918	$ 133,681	$ 133,681
Effect of foreign exchange rate changes	1,460	1,460
Other	756	756
Balance at the end of the period	$ 278,815	$ 145,134	$ 133,681	$ 133,681

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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

-Publisher FASB

-Name Accounting Standards Codification

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Amount of other (increase) decrease of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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Amount of increase (decrease) from foreign currency translation adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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