Summary of Significant Accounting Policies Accounting Policies (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Accounting Policies [Abstract]
Outgoing freight expenses	$ 44,672	$ 40,896	$ 35,683
Goodwill	$ 6,680	$ 6,680

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

Cost incurred during the reporting period in transporting goods and services to customers. Includes freight-out costs.

+ References

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+ Details