The number of shares purchased by employees under the investment share purchase program.

No definition available.

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- Definition

Share based compensation arrangement by share based payment award, fair value assumptions, estimated forfeiture rate.

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No definition available.

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Share based compensation arrangement by share based payment award participants payment description.

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Employee tenure requirement to participate in plan.

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- Definition

Stock repurchase program, cumulative number of shares repurchased.

+ References

No definition available.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
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- Definition

Discount rate from fair value on purchase date that participants pay for shares.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- 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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No definition available.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Gross number of share options (or share units) granted during the period.

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- Definition

Number of options outstanding, including both vested and non-vested options.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-SubTopic 10
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-Subparagraph (c)(1)(ii)
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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-Section 50
-Paragraph 2
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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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- Definition

Number of options vested.

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No definition available.

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- Definition

Weighted average grant-date fair value of options vested.

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No definition available.

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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Common Stock and Share-Based Compensation - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
	Dec. 25, 2021	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, contractual term		5 years 3 months
Other than options granted in period		43,589
Stock option outstanding	221,354	204,245	221,354
Weighted average fair value of stock awards		$ 346.09
Weighted average exercise price	$ 310.38	$ 334.26	$ 310.38
Expected dividends		0.00%	0.00%	0.00%
Estimated forfeiture rate for equity awards that do not vest on January 1st		19.00%	13.00%	13.00%
Total fair value of options vested in period	$ 6,300,000	$ 6,600,000		$ 4,800,000
Aggregate intrinsic value of stock options exercised in period		6,900,000	$ 28,900,000	$ 45,900
Unrecognized compensation costs		$ 23,700,000
Unrecognized compensation costs, weighted average period		2 years
Option vested, number of shares		32,476	42,038	45,860
Option vested, weighted average fair value		$ 292.27	$ 227.40	$ 214.23
Repurchase of shares		13,800,000
Stock repurchased during period		0	0	0
Performance-Based Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option outstanding		17,114
Performance-Based Awards \| Board of Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option outstanding		7,147
Non-Employee Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted in period		3,810	1,422	4,410
Non-Employee Director \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, contractual term		10 years
Employee Stock Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted in period		17,114	18,998	21,992
Employee Stock Compensation Plan \| Investment Share Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		5 years
Share based compensation arrangement by share based payment award participants payment description		Participants may pay for these shares either up front or through payroll deductions over an eleven-month period during the year of purchase.
Shares employees elected to purchase		10,845	4,954	9,127
Employee Stock Compensation Plan \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Employee Stock Compensation Plan \| Minimum \| Investment Share Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requirement tenure of employee for investment share program, purchase shares at discount		1 year
Discount from current market value		0.00%
Employee Stock Compensation Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		5 years
Stock options, contractual term		10 years
Employee Stock Compensation Plan \| Maximum \| Investment Share Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Discount from current market value		40.00%
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options granted in period		32,744	12,867	33,403
Restricted Stock Units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Restricted Stock Units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		5 years
Common Class A \| Non-Employee Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance	600,000		600,000
Shares available for grant	100,000		100,000
Common Class A \| Employee Stock Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance		6,700,000
Shares available for grant		1,000,000.0