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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

Aggregate number of common shares reserved for future issuance.

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Net number of non-option equity instruments granted to participants.

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- Definition

Number of shares issued under share-based payment arrangement.

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- Definition

Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

+ References

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- Definition

Number of shares issued which are neither cancelled nor held in the treasury.

+ References

No definition available.

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- Definition

Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

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No definition available.

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- Definition

Number of shares (or other type of equity) forfeited during the period.

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No definition available.

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- Definition

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

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No definition available.

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

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Number of shares that have been repurchased during the period and are being held in treasury.

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Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019	Dec. 04, 2019	Sep. 30, 2019	May 02, 2019	Feb. 06, 2019	Dec. 31, 2018	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
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted			69,338
Shares, Issued						39,767			264,815
Shares Issued, Shares, Share-based Payment Arrangement, Forfeited			97,983
Shares, vested			49,678
Shares, Outstanding	156,921		156,921
Treasury Stock Acquired, Average Cost Per Share	$ 22.60	$ 16.70	$ 22.59	$ 16.58
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 3,545		$ 3,545
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation			17,427	87,609
Common Stock, Capital Shares Reserved for Future Issuance	731,443		731,443
Stock Repurchase Program, Number of Shares Authorized to be Repurchased	1,500,000		1,500,000					1,000,000.0
Treasury Stock Acquired, Average Cost Per Share	$ 22.60	$ 16.70	$ 22.59	$ 16.58
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation			17,427	87,609
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 3,545		$ 3,545
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Expense	429	$ 111	795	$ 111
Phantom Share Units (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Expense	96	50	197	99
Performance Based Phantom Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Expense	$ 187	$ 465	$ 615	$ 465
Treasury Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Treasury Stock, Shares, Acquired	178,431	191,442	215,675	323,563
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period			113,408	212,688
Shares, Issued	977,863	667,682	977,863	667,682	826,353		884,518			763,426	843,993
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			5,750
Share-based Payment Arrangement, Nonemployee [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, Issued	3,172		3,172
Share Repurchase Program [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Treasury Stock, Shares, Acquired	178,431	189,821	198,248	235,954
Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Shares Authorized	3,000,000.0		3,000,000.0
Chief Executive Officer [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
President [Member] \| Treasury 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				3,991