XML 120 R103.htm IDEA: XBRL DOCUMENT
v3.21.1

Net Income per Share - Schedule of Issuable Weighted Average Share Information (Details) - shares | 12 Months Ended
--- | ---
Mar. 26, 2021 | Mar. 27, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Dilutive effect of common stock equivalents (in shares) | 92,968,590 | 0
Common Class A And Common Class L |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Dilutive effect of common stock equivalents (in shares) | 92,438,187 | 0
Restricted Stock Units (RSUs) |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Dilutive effect of common stock equivalents (in shares) | 308,811 | 0
Performance Stock Units (PSUs) |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Dilutive effect of common stock equivalents (in shares) | 218,678 | 0
Employee Stock Purchase Plan (ESPP) |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Dilutive effect of common stock equivalents (in shares) | 2,914 | 0

X
- Definition Weighted Average Number Issuable Shares Outstanding Adjustment + References No definition available. + Details
Name: | algm_WeightedAverageNumberIssuableSharesOutstandingAdjustment
Namespace Prefix: | algm_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- 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_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=algm_CommonClassAAndCommonClassLMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=us-gaap_RestrictedStockUnitsRSUMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=us-gaap_PerformanceSharesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=us-gaap_EmployeeStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |