v3.25.4

Debt (Narratives) (Details) - USD ($)		3 Months Ended		6 Months Ended
	Jun. 22, 2023	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2025	Dec. 31, 2024
Line Of Credit Facility [Line Items]
Payments of lines of credit				$ 25,000,000
Borrowings under revolving facility				25,000,000
Outstanding letters of credit		$ 14,200,000		$ 14,200,000
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				5.92%	6.84%
Amended Credit Agreement | Interest Expense
Line Of Credit Facility [Line Items]
Amortization of deferred financing costs		300,000	$ 300,000	$ 600,000	$ 600,000
Amended Credit Agreement | Term Loan
Line Of Credit Facility [Line Items]
Payments of lines of credit		0	$ 0	0	$ 0
Amended Credit Agreement | Revolving Facility
Line Of Credit Facility [Line Items]
Borrowing capacity from Credit Agreement		135,800,000		135,800,000
Outstanding letters of credit		$ 0		$ 0
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%

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- Definition

Debt instrument, spread adjustment.

+ References

No definition available.

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- Definition

Debt instrument, subject to floor.

+ References

No definition available.

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- Definition

Line of credit additional incremental loan facility.

+ References

No definition available.

+ Details

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Namespace Prefix:	extr_
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Balance Type:	credit
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- Definition

Amount of amortization expense attributable to debt issuance costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

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

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

+ References

No definition available.

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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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
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X

- 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

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

- 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

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- 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
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