Acquisitions - Summary of preliminary purchase price allocation (Details) (Salvage vehicle auction business in Brazil and auction platform in Germany, USD $) In Thousands, unless otherwise specified	Apr. 30, 2013
Salvage vehicle auction business in Brazil and auction platform in Germany
Business Acquisition [Line Items]
Total cash paid, net of cash acquired	$ 31,243
Contingent consideration	3,690
Total acquisition price	34,933
Allocation of the acquisition price:
Accounts receivable and prepaid expenses	848
Property and equipment	15,425
Intangible assets	9,197
Goodwill recorded during the period	13,456
Liabilities assumed	(3,993)
Fair value of net assets and liabilities acquired	$ 34,933

The amount of acquisition cost of a business combination allocated to accounts receivable and prepaid expenses.

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The total cash paid to shareholders of acquired entities net of cash acquired.

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Fair value, as of the acquisition date, of potential payments under the contingent consideration arrangement including cash and shares.

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The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

+ References

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The total purchase price of the acquired entity. This includes cash paid to equity interest holders of the acquired entity, fair value of debt and equity securities issued to equity holders of the acquired entity, and transaction costs paid to third parties to consummate the acquisition.

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Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

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Amount of acquisition cost of a business combination allocated to assets, excluding financial assets and goodwill, lacking physical substance.

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The amount of acquisition cost of a business combination allocated to liabilities assumed.

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The amount of acquisition cost of a business combination allocated to property, plant and equipment to be used in ongoing operations.

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