Shares, vested

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

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

+ Details

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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.

+ Details

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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.

+ References

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, 2022	Mar. 31, 2021	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	May 02, 2019	Sep. 30, 2016
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			3,118
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted			0
Shares Issued, Shares, Share-based Payment Arrangement, Forfeited			4,962
Shares, vested			106,964
Shares, Outstanding	321,463		321,463
Treasury Stock Acquired, Average Cost Per Share		$ 49.00		$ 46.81
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 95		$ 95
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation			45,198	16,882
Common Stock, Capital Shares Reserved for Future Issuance	713,151		713,151
Stock Repurchase Program, Number of Shares Authorized to be Repurchased									1,000,000.0	1,500,000
Treasury Stock Acquired, Average Cost Per Share		$ 49.00		$ 46.81
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation			45,198	16,882
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 95		$ 95
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period		13,996
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross			150,447
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Expense	36	$ 36	$ 71	$ 74
Phantom Share Units (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Expense	96	90	193	186
Performance Based Phantom Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Expense	$ 864	$ 711	$ 1,632	$ 1,408
Treasury Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Treasury Stock, Shares, Acquired	2,587		104,200	30,878
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period			73,627	38,087
Shares, Issued	1,264,031	1,210,685	1,264,031	1,210,685	1,261,444	1,316,998	1,279,545	1,287,134
Share-based Payment Arrangement, Nonemployee [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, Issued		380		380
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			83,540	68,860
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	2,587		59,002