Debt Instrument, Interest Rate Floor

No definition available.

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Period Type:	instant

- 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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Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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Balance Type:	debit
Period Type:	instant

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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+ Details

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

- 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://fasb.org/us-gaap/role/ref/legacyRef
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+ Details

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

- Definition

The effective interest rate at the end of the reporting period.

+ References

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
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.

+ References

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityLineItems
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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

The cash outflow to repay long-term debt that is wholly or partially secured by collateral. Excludes repayments of tax exempt secured debt.

+ References

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+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

+ Details

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Balance Type:	debit
Period Type:	instant

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

Name:	us-gaap_CreditFacilityAxis=algm_UnsecuredRevolvingCreditFacilitiesMember
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- Details

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- Details

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- Details

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- Details

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- Details

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Debt and Other Borrowings - Senior Secured Credit Facilities (Details)					12 Months Ended
	Nov. 25, 2020 USD ($)	Sep. 30, 2020 USD ($)	Jan. 22, 2019 USD ($)	Mar. 27, 2006 USD ($)	Mar. 25, 2022 USD ($)	Mar. 26, 2021 USD ($)	Mar. 27, 2020 USD ($)	Sep. 16, 2020	Nov. 26, 2019 PHP (₱)	Nov. 20, 2019 PHP (₱)	Dec. 05, 2001 USD ($)
Line of Credit Facility [Line Items]
Repayment of senior secured debt					$ 0	$ 300,000,000	$ 0
Loss on debt extinguishment					$ 0	9,055,000	0
Senior Secured Term Loan \| Credit Suisse AG, Cayman Islands Branch
Line of Credit Facility [Line Items]
Maximum borrowing capacity		$ 325,000,000
Repayment of senior secured debt	$ 300,000,000
Deferred financing costs		9,374,000
Loss on debt extinguishment						9,055,000
Senior Secured Revolving Credit Facility \| Mizuho Bank, Ltd
Line of Credit Facility [Line Items]
Maximum borrowing capacity		50,000,000
Interest rate at period end					4.25%
Outstanding balance					$ 0
Deferred financing costs		$ 300,000
Unamortized deferred financing costs					149,000	249,000
Senior Secured Revolving Credit Facility \| Mizuho Bank, Ltd \| LIBOR
Line of Credit Facility [Line Items]
Interest rate floor		0.005
Senior Secured Revolving Credit Facility \| Mizuho Bank, Ltd \| LIBOR \| Minimum
Line of Credit Facility [Line Items]
Basis spread on variable rate		3.75%
Senior Secured Revolving Credit Facility \| Mizuho Bank, Ltd \| LIBOR \| Maximum
Line of Credit Facility [Line Items]
Basis spread on variable rate		4.00%
Line of Credit \| Mizuho Bank, Ltd
Line of Credit Facility [Line Items]
Repayment of senior secured debt		$ 25,000,000
Line of Credit \| Bank Of Mitsubishi UFJ
Line of Credit Facility [Line Items]
Repayment of senior secured debt		$ 8,000,000
Unsecured Revolving Credit Facilities \| Line-of-Credit Agreement Expiring January 22, 2021 \| Line of Credit
Line of Credit Facility [Line Items]
Maximum borrowing capacity			$ 25,000
Outstanding balance						25,000,000	$ 25,000,000
Unsecured Revolving Credit Facilities \| Line-of-Credit Agreement Due at Various Times During Fiscal Year 2021 \| Line of Credit
Line of Credit Facility [Line Items]
Maximum borrowing capacity				$ 10,000
Interest rate at period end							1.70%	2.50%
Outstanding balance							$ 10,000,000
Unsecured Revolving Credit Facilities \| Line-of-Credit Agreement Maturing June 18, 2020 \| Line of Credit
Line of Credit Facility [Line Items]
Maximum borrowing capacity											$ 8,000,000
Interest rate at period end							1.90%
Outstanding balance							$ 8,000,000
Unsecured Revolving Credit Facilities \| Line-of-Credit Agreement Expiring August 31, 2021 \| Line of Credit
Line of Credit Facility [Line Items]
Maximum borrowing capacity					1,145,000				₱ 60,000,000
Outstanding balance					0	0
Unsecured Revolving Credit Facilities \| Line-of-Credit Agreement Expiring June 30, 2021 \| Line of Credit
Line of Credit Facility [Line Items]
Maximum borrowing capacity					1,431,000					₱ 75,000,000
Outstanding balance					$ 0	$ 0
Unsecured Revolving Credit Facilities \| LIBOR \| Line-of-Credit Agreement Expiring January 22, 2021 \| Line of Credit
Line of Credit Facility [Line Items]
Basis spread on variable rate			0.40%
Unsecured Revolving Credit Facilities \| LIBOR \| Line-of-Credit Agreement Due at Various Times During Fiscal Year 2021 \| Line of Credit
Line of Credit Facility [Line Items]
Basis spread on variable rate				1.00%