Components of Net Pension Cost (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 178	$ 151
Interest cost	45	249
Amortization of losses	2	115
Expected return on assets	(77)	(235)
Net periodic pension cost	148	280
Settlement loss	87
Total pension cost	$ 235	$ 280