Aggregate Purchase Price Paid for Acquisitions and Other Adjustments to Consideration (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012
Business Acquisition [Line Items]
Cash	$ 153,390
Promissory notes	24,496
Deferred consideration	19,181
Contingent consideration	18,585
Total purchase price	$ 215,652

Fair Value of the liabilities incurred by the acquirer to former owners of the acquiree, including the fair value of any contingent consideration. If liabilities transferred as consideration remain within the combined entity after the business combination (for example, because the assets or liabilities were transferred to the acquiree rather than to its former owners), and the acquirer therefore retains control of them; in that situation, the acquirer measures those liabilities at their carrying amounts immediately before the acquisition date.

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+ Details