Fair Value Measurements (Narrative) (Detail) - USD ($) shares in Thousands, $ in Thousands	1 Months Ended		3 Months Ended
	Mar. 21, 2017	Dec. 21, 2016	Sep. 30, 2017	Sep. 30, 2016	Nov. 30, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unrealized loss on interest rate swap			$ (475)
Accrued contingent consideration			3,077
Aggregate principal amount					$ 143,750
Theoretical borrowing rate used to calculate fair value of debt					6.50%
Fair value of the notes			129,000
Fair value of future issuance of shares			90,400
Foreign currency contract
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, notional amount			48,816
Unrealized losses on hedging activities			295	$ (36)
Cash flow hedging | December 21, 2021 | Interest rate swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Additional interest cost rate of derivative	2.005%
Derivative, notional amount	$ 100,000
Derivative, expiration date	Dec. 21, 2021
Remaining balance of derivative			92,500
France Company
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Accrued contingent consideration			153	$ 135
Citron and Lucid
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Accrued contingent consideration			$ 2,924
Number of shares to be issued		5,122