Fair Value Measurements (Narratives) (Details) - USD ($)	3 Months Ended	12 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Jun. 30, 2023
Not Designated as Hedging Instrument \| Forward Foreign Currency Contracts
Assets/Liabilities
Notional principal amount of forward foreign exchange contracts	$ 18,700,000		$ 3,400,000
Maximum maturities for contracts	40 days		40 days
Gains (losses) on foreign currency derivative instruments		$ (500,000)
Not Designated as Hedging Instrument \| Forward Foreign Currency Contracts \| Maximum
Assets/Liabilities
Gains (losses) on foreign currency derivative instruments	$ (100,000)
Designated as Hedging Instrument \| Forward Foreign Currency Contracts
Assets/Liabilities
Unrealized gain (loss) on derivatives	0		$ 0
Level 2 Assets and Liabilities
Assets/Liabilities
Long-term debt, fair value	197,500,000		225,000,000
Transfers of assets between Level 1 and Level 2	0	0
Transfers of liabilities between Level 1 and Level 2	0	0
Level 3 Assets and Liabilities
Assets/Liabilities
Fair value, measurement level 3 assets, transfers	0		0
Fair value, measurement level 3 liabilities transfers	0		0
Transfers of assets between Level 2 and Level 3	0	0
Transfers of liabilities between Level 2 and Level 3	0	0
Fair value assets impairment	0	$ 0
Recurring
Assets/Liabilities
Certificate of deposits	5,583,000		7,151,000
Recurring \| Level 2 Assets and Liabilities
Assets/Liabilities
Certificate of deposits	$ 5,583,000		$ 7,151,000

Certificates of deposit at fair value.

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- Definition

Total loss recognized during the period from the loss recognized in the period resulting from the impairment of the fair valued assets.

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- Definition

Fair value assets level1 to level2 transfer amount.

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Fair value assets Level 2 to Level 3 transfers amount.

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Fair value liabilities Level 2 to Level 3 transfers amount.

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Fair value liability level1 to level2 transfer amount.

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
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Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy.

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Amount of transfers of financial instrument classified as a liability into (out of) level 3 of the fair value hierarchy.

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Amount of gain (loss) recognized in earnings in the period from the increase (decrease) in fair value of foreign currency derivatives not designated as hedging instruments.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Maximum amount of time remaining before foreign currency exchange rate derivatives mature or expire, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

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