Reconciliation of Beginning and Ending Amount of Consolidated Liability for Unrecognized Income Tax Benefits (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
Reconciliation of Unrecognized Tax Benefits [Line Items]
Beginning Balance	$ 11,000	$ 14,968	$ 11,463
Additions for tax positions of prior years	489	631	3,793
Additions for tax positions related to current year		242	468
Reductions for tax positions of prior years			(59)
Reductions from lapses in statutes of limitations	(3,732)	(961)	(413)
Reductions from settlements with taxing authorities	(3,700)	(4,002)	(197)
Foreign exchange rate adjustment	(152)	122	(87)
Ending Balance	7,605	11,000	14,968
Unrecognized Tax Benefit
Reconciliation of Unrecognized Tax Benefits [Line Items]
Beginning Balance	9,011	12,816	9,794
Additions for tax positions of prior years	242	184	3,287
Additions for tax positions related to current year		242	468
Reductions for tax positions of prior years			(40)
Reductions from lapses in statutes of limitations	(3,125)	(961)	(413)
Reductions from settlements with taxing authorities		(3,392)	(193)
Foreign exchange rate adjustment	(167)	122	(87)
Ending Balance	5,961	9,011	12,816
Interest and Penalties
Reconciliation of Unrecognized Tax Benefits [Line Items]
Beginning Balance	1,989	2,152	1,669
Additions for tax positions of prior years	247	447	506
Reductions for tax positions of prior years			(19)
Reductions from lapses in statutes of limitations	(607)
Reductions from settlements with taxing authorities		(610)	(4)
Foreign exchange rate adjustment	15
Ending Balance	$ 1,644	$ 1,989	$ 2,152