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Net (Loss) Income per Share - Additional Information (Detail) - shares |  |  |  |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | --- | --- | --- | ---
Mar. 01, 2021 | Mar. 01, 2020 | Mar. 01, 2019 | Jan. 01, 2019 | Sep. 25, 2021 | Sep. 26, 2020 | Sep. 25, 2021 | Sep. 26, 2020
Common Class A |  |  |  |  |  |  |  |
Earnings Per Share Note [Line Items] |  |  |  |  |  |  |  |
Antidilutive securities excluded from computation of earnings per share |  |  |  |  |  | 0 | 16,000 | 1,000
Unvested or Unexercised Securities |  |  |  |  |  |  |  |
Earnings Per Share Note [Line Items] |  |  |  |  |  |  |  |
Antidilutive securities excluded from computation of earnings per share |  |  |  |  | 182,000 |  |  |
Investment Share Program |  |  |  |  |  |  |  |
Earnings Per Share Note [Line Items] |  |  |  |  |  |  |  |
Vesting period |  |  |  |  |  |  | 5 years |
Investment Share Program | Minimum |  |  |  |  |  |  |  |
Earnings Per Share Note [Line Items] |  |  |  |  |  |  |  |
Requirement tenure of employee for investment share program, purchase shares at discount |  |  |  |  |  |  | 1 year |
Discount from current market value |  |  |  |  |  |  | 20.00% |
Investment Share Program | Maximum |  |  |  |  |  |  |  |
Earnings Per Share Note [Line Items] |  |  |  |  |  |  |  |
Requirement tenure of employee for investment share program, purchase shares at discount |  |  |  |  |  |  | 2 years |
Discount from current market value |  |  |  |  |  |  | 40.00% |
Restricted Stock Awards |  |  |  |  |  |  |  |
Earnings Per Share Note [Line Items] |  |  |  |  |  |  |  |
Vesting period | 4 years | 4 years | 4 years | 5 years |  |  |  |

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- Definition Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=124432515&loc=d3e3550-109257 + Details
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- Definition Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Discount rate from fair value on purchase date that participants pay for shares. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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