Amount of cost for defined contribution plan.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 70
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480794/715-70-50-1

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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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- Definition

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

+ References

No definition available.

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- Definition

Percentage employer matches of the employee's percentage contribution matched.

+ References

No definition available.

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Pension Plan and Retirement Benefits - Defined Contribution Plans (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Defined Contribution 401K Plan [Member]
Defined Contribution Plans
Expenses associated with plan			$ 2,352	$ 2,016	$ 1,748
Defined Contribution 401K Plan [Member] \| Employees with exceptions
Defined Contribution Plans
Percentage employer matches of the employee's percentage contribution matched.			50.00%
Defined Contribution 401K Plan [Member] \| Employees with exceptions \| Maximum
Defined Contribution Plans
Percentage of employees' gross pay for which the employer contributes a matching contribution			3.00%
Defined Contribution 401K Plan [Member] \| Certain employees not eligible for U.S. pension plan
Defined Contribution Plans
Percentage employer matches of the employee's percentage contribution matched.	60.00%	60.00%
Defined Contribution 401K Plan [Member] \| Certain employees not eligible for U.S. pension plan \| Maximum
Defined Contribution Plans
Percentage of employees' gross pay for which the employer contributes a matching contribution	8.00%	6.00%
Profit Sharing Plans [Member]
Defined Contribution Plans
Expenses associated with plan			$ 0	$ 0	$ 0