Debt instrument, spread adjustment.

No definition available.

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument, subject to floor.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of credit additional incremental loan facility.

+ References

No definition available.

+ Details

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Namespace Prefix:	extr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage of consolidated earnings before interest, taxes, depreciation, and amortization for incremental loan commitment.

+ References

No definition available.

+ Details

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Namespace Prefix:	extr_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of amortization expense attributable to debt issuance costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
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-Name Accounting Standards Codification
-Section 45
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482925/835-30-45-3

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Incremental percentage increase (decrease) in the stated rate on a debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 944
-SubTopic 605
-Name Accounting Standards Codification
-Section 55
-Paragraph 15
-Publisher FASB
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-URI https://asc.fasb.org/1943274/2147477548/944-605-55-12

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
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-Paragraph 1
-Publisher FASB
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 8
-Publisher FASB
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-Paragraph 1
-Subparagraph (SX 210.5-02(19)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Period remaining before termination of line of credit facility, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477657/942-210-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Section S50
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 235
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-SubTopic 10
-Name Accounting Standards Codification
-Section S99
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-Topic 470
-SubTopic 10
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-Section 50
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-Subparagraph (b)
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-Topic 470
-SubTopic 10
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-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-14

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-15

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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- Details

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Balance Type:
Period Type:

- Details

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Debt (Narratives) (Details) - USD ($)			12 Months Ended
Debt (Narratives) (Details) - USD ($)	Jul. 29, 2026	Jun. 22, 2023	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2024
Line Of Credit Facility [Line Items]
Borrowings under revolving facility			$ 55,000,000		$ 30,000,000
Payments of lines of credit			55,000,000		55,000,000
Outstanding letters of credit			$ 14,400,000
Credit Agreement \| Applicable Margin for SOFR
Line Of Credit Facility [Line Items]
Debt instrument, subject to floor		0.00%
Debt instrument, spread adjustment		0.10%
Credit Agreement \| Term Loan
Line Of Credit Facility [Line Items]
Borrowing capacity from Credit Agreement		$ 200,000,000
Credit Agreement \| Revolving Facility
Line Of Credit Facility [Line Items]
Credit Facility, term		5 years
Borrowing capacity from Credit Agreement		$ 150,000,000
Amended Credit Agreement
Line Of Credit Facility [Line Items]
Debt instrument interest rate			5.77%	6.43%
Amended Credit Agreement \| Location, Statement of Income, Balance [Axis]: us-gaap:InterestExpense
Line Of Credit Facility [Line Items]
Amortization of deferred financing costs			$ 1,200,000	$ 1,200,000	$ 1,100,000
Amended Credit Agreement \| Term Loan
Line Of Credit Facility [Line Items]
Payments of lines of credit			0	$ 0
Amended Credit Agreement \| Revolving Facility
Line Of Credit Facility [Line Items]
Revolving loans outstanding			0
Borrowing capacity from Credit Agreement			$ 135,600,000
Subsequent Event \| 2026 Credit Agreement \| Revolving Facility
Line Of Credit Facility [Line Items]
Credit Facility, term	5 years
Borrowing capacity from Credit Agreement	$ 500,000,000
Borrowings under revolving facility	200,000,000
Additional incremental loan facility	$ 175,000,000
Percentage of consolidated EBITDA	100.00%
Revolving loans outstanding	$ 200,000,000
Remained available for borrowing	$ 300,000,000
Maximum \| Credit Agreement
Line Of Credit Facility [Line Items]
Additional incremental loan facility		$ 100,000,000
Maximum \| Credit Agreement \| Applicable Margin for Base Rate
Line Of Credit Facility [Line Items]
Borrowings, interest rate		1.75%
Maximum \| Credit Agreement \| Applicable Margin for SOFR
Line Of Credit Facility [Line Items]
Borrowings, interest rate		2.75%
Minimum \| Credit Agreement \| Applicable Margin for Base Rate
Line Of Credit Facility [Line Items]
Borrowings, interest rate		1.00%
Minimum \| Credit Agreement \| Applicable Margin for SOFR
Line Of Credit Facility [Line Items]
Borrowings, interest rate		2.00%