Employee Benefit Plans - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2011
Pension and Other Postretirement Benefits Disclosure [Line Items]
Number of defined benefit pension plans	3
Defined Contribution Plan	2
K 401 Plan
Pension and Other Postretirement Benefits Disclosure [Line Items]
Contribution to pension plans	$ 1,061	$ 1,378	$ 1,301
Pension Plans
Pension and Other Postretirement Benefits Disclosure [Line Items]
Additional Contribution to pension plans	2,100
SERP
Pension and Other Postretirement Benefits Disclosure [Line Items]
Additional Contribution to pension plans	$ 677