Employee Pension Plan (Details) (Employee Pension Plan [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Employee Pension Plan [Member]
Components of net periodic benefit cost:
Service cost
Interest cost	714	748	2,142	2,244
Expected return on plan assets	(941)	(879)	(2,823)	(2,637)
Net amortization	688	691	2,064	2,073
Net periodic benefit cost	$ 461	$ 560	$ 1,383	$ 1,680