Goodwill (Details) (USD $)	9 Months Ended
Sep. 30, 2011	Dec. 31, 2010
Goodwill [Line Items]
Gross goodwill	$ 236,576,000	$ 236,576,000
Accumulated impairment losses	(9,713,000)	(9,713,000)
Goodwill, net	226,863,000	226,863,000
Goodwill, impairment loss	0
Pricing and Revenue Management [Member]
Goodwill [Line Items]
Goodwill, net	3,700,000
Supply Chain [Member]
Goodwill [Line Items]
Goodwill, net	$ 223,300,000

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

Loss recognized during the period that results from the write-down of goodwill after comparing the implied fair value of reporting unit goodwill with the carrying amount of that goodwill. Goodwill is assessed at least annually for impairment.

+ References

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+ Details