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Net Income per Share - Additional Information (Detail) |  |  |  | 3 Months Ended | 6 Months Ended
--- | --- | --- | --- | --- | ---
Mar. 01, 2020 | Mar. 01, 2019 | Jan. 01, 2019 | Jun. 27, 2020 employee shares | Jun. 29, 2019 shares | Jun. 27, 2020 employee shares | Jun. 29, 2019 shares
Investment Share Program |  |  |  |  |  |  |
Earnings Per Share Note [Line Items] |  |  |  |  |  |  |
Vesting period |  |  |  |  |  | 5 years |
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% |
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% |
Restricted Stock Awards |  |  |  |  |  |  |
Earnings Per Share Note [Line Items] |  |  |  |  |  |  |
Vesting period | 4 years | 4 years | 5 years |  |  |  |
Common Class A |  |  |  |  |  |  |
Earnings Per Share Note [Line Items] |  |  |  |  |  |  |
Antidilutive securities excluded from computation of earnings per share |  |  |  | 23,000 | 10,000 | 16,000 | 6,000
Common Class A | Performance-Based Awards |  |  |  |  |  |  |
Earnings Per Share Note [Line Items] |  |  |  |  |  |  |
Number of shares not included because the performance criteria was not expected to be met |  |  |  |  |  |  | 18,000
Common Class A | Performance-Based Awards | Key employee |  |  |  |  |  |  |
Earnings Per Share Note [Line Items] |  |  |  |  |  |  |
Number Of Employees | employee |  |  |  | 1 |  | 1 |

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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=6371337&loc=d3e3550-109257 + Details
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