Debt Instrument, Number Of Covenants

No definition available.

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Namespace Prefix:	alg_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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Period Type:	instant

- 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

Amount of the required periodic payments including both interest and principal payments.

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Balance Type:	debit
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- Definition

Period between issuance and maturity of debt instrument, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

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- Definition

The maximum amount of borrowing capacity under a line of credit that is available as of the balance sheet date for financing purchases of goods acquired for inventory or imminent delivery to a customer.

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- Definition

Fair value of the amount outstanding under the credit facility.

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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.

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

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

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- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt classified as noncurrent. Excludes lease obligation.

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Debt - Additional Information (Details) $ in Thousands	May 27, 2026 USD ($) covenant	Jun. 30, 2026 USD ($)
Bank revolving credit facility \| Fourth Amended And Restated Revolving Credit Agreement
Debt Instrument [Line Items]
Number of covenants \| covenant	2
Standby Letters of Credit
Debt Instrument [Line Items]
Amount of capacity		$ 3,200
Standby Letters of Credit \| Bank revolving credit facility \| Fourth Amended And Restated Revolving Credit Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 400,000
Revolving Line of Credit
Debt Instrument [Line Items]
Available borrowings		334,300
Line of Credit \| Bank revolving credit facility
Debt Instrument [Line Items]
Long-term debt, excluding current maturities		62,500
Line of Credit \| Bank revolving credit facility \| Fourth Amended And Restated Revolving Credit Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity	602,500
Unused borrowing capacity, amount	$ 400,000
Fair value of amount outstanding		263,700
Line of Credit \| Bank revolving credit facility \| Fourth Amended And Restated Revolving Credit Agreement \| Minimum
Debt Instrument [Line Items]
Commitment fee percentage	0.125%
Line of Credit \| Bank revolving credit facility \| Fourth Amended And Restated Revolving Credit Agreement \| Minimum \| Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Interest rate	1.25%
Line of Credit \| Bank revolving credit facility \| Fourth Amended And Restated Revolving Credit Agreement \| Minimum \| Base Rate
Debt Instrument [Line Items]
Interest rate	0.25%
Line of Credit \| Bank revolving credit facility \| Fourth Amended And Restated Revolving Credit Agreement \| Maximum
Debt Instrument [Line Items]
Commitment fee percentage	0.30%
Line of Credit \| Bank revolving credit facility \| Fourth Amended And Restated Revolving Credit Agreement \| Maximum \| Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Interest rate	2.25%
Line of Credit \| Bank revolving credit facility \| Fourth Amended And Restated Revolving Credit Agreement \| Maximum \| Base Rate
Debt Instrument [Line Items]
Interest rate	1.25%
Term Facility \| Bank revolving credit facility \| Fourth Amended And Restated Revolving Credit Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 202,500
Periodic payment	$ 1,270
Debt term	5 years
Fair value of amount outstanding		$ 201,200