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No definition available.

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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

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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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.

+ References

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.

+ References

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.

+ References

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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- Definition

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, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	May 02, 2019	Sep. 30, 2015
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, Shares Issued in Period			8,183
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted			0
Shares Issued, Shares, Share-based Payment Arrangement, Forfeited			114,067
Shares, vested			87,769
Shares, Outstanding	291,586		291,586
Treasury Stock Acquired, Average Cost Per Share		$ 22.60		$ 22.59
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 238		$ 238
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation			16,882	17,427
Common Stock, Capital Shares Reserved for Future Issuance	828,238		828,238
Stock Repurchase Program, Number of Shares Authorized to be Repurchased									1,000,000.0	1,500,000
Treasury Stock Acquired, Average Cost Per Share		$ 22.60		$ 22.59
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation			16,882	17,427
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 238		$ 238
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period			13,996
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Expense	36	$ 429	$ 74	$ 795
Phantom Share Units (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Expense	90	96	186	197
Performance Based Phantom Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Expense	$ 711	$ 187	$ 1,408	$ 615
Treasury Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Treasury Stock, Shares, Acquired		178,431	30,878	215,675
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period			38,087	113,408
Shares, Issued	1,210,685	977,863	1,210,685	977,863	1,279,545	1,287,134	826,353	884,518
Share-based Payment Arrangement, Nonemployee [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, Issued	380	3,172	380	3,172
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			68,860	5,750
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
Repurchase Agreements [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Treasury Stock, Shares, Acquired	0	178,431		198,248