Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable Securities, short-term	$ 2,750
Level 1 | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents	247,566
Marketable Securities, short-term	2,750
Total Financial Assets and Liabilities at Fair Value	250,316
Level 3 | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
ATC Earn-out Liability	4,579
FAVIP Contingent Consideration	2,765
Total Financial Assets and Liabilities at Fair Value	$ 7,344