Employee Benefit Plans (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Defined Contribution Pension and Other Postretirement Plans Disclosure [Abstract]
Maximum contribution by employee (as a percent)	75.00%
Maximum matching contribution by employer (as a percent)	4.00%
Employer's contribution	$ 1,014	$ 936	$ 890

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

No definition available.

Name:	us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration