Funded Status and Amounts Recognized in Consolidated Balance Sheet (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at beginning of year	$ 28,068	$ 15,914
Acquisition date benefit obligations from entities acquired during the fiscal year		10,354
Service cost	787	216	100
Interest cost	984	796	775
Actuarial loss	1,235	2,138
Benefits paid	(2,203)	(356)
Settlement loss	1,040
Settlements paid	(18,928)
Foreign currency translation	(802)	(994)
Benefit obligation at end of year	10,181	28,068	15,914
Fair value of assets at beginning of year	20,173	9,990
Acquisition date fair value of assets for entities acquired during the fiscal year		9,226
Actual return on plan assets	1,446	1,322
Disbursements	(2,463)	(356)
Employer contributions	7,684	778
Employee contributions	334	76
Settlements paid	(18,928)
Foreign currency translation	(231)	(863)
Fair value of assets at end of year	8,015	20,173	9,990
Funded status/accrued benefit liability	$ (2,166)	$ (7,895)