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Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	May 20, 2019	May 02, 2019	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Shares Authorized	100,000,000		100,000,000				100,000,000
Common Stock, Capital Shares Reserved for Future Issuance	847,891		847,891
Stock Repurchase Program, Number of Shares Authorized to be Repurchased	1,500,000		1,500,000		1,000,000	1,000,000
Treasury Stock Acquired, Average Cost Per Share	$ 17.88	$ 15.45	$ 17.11	$ 15.41
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation			87,609	32,832
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 3,352		$ 3,352
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period			59,924
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Expense	333	$ 11	$ 443	$ 256
Phantom Share Units (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Expense	100	49	$ 200	140
Performance Based Phantom Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period			230,274
Share-based Payment Arrangement, Expense	$ 427	$ 343	$ 892	$ 792
Treasury Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Treasury Stock, Shares, Acquired	162,993	53,642	486,556	133,459
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period			212,688
Treasury Stock [Member] \| Phantom Share Units (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period			3,991
Share-based Payment Arrangement, Employee [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period				1,500
Share-based Payment Arrangement, Nonemployee [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period				520
Share Repurchase Program [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Treasury Stock, Shares, Acquired	162,993	20,810	398,947	100,627
Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Shares Authorized	3,000,000		3,000,000
Chief Executive Officer [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period			283,195
Chief Executive Officer [Member] \| Performance Based Phantom Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, Outstanding	170,350		170,350