Employee Benefit Plans Components of Net Pension Cost (Detail) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Compensation and Retirement Disclosure [Abstract]
Service cost	$ 136	$ 119
Interest cost	18	31
Amortization of losses	4	0
Expected return on assets	(40)	(53)
Net periodic pension cost	$ 118	$ 97