Schedule Of Share Based Compensation Arrangements [Line Items]

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- Definition

Share-based compensation arrangement by share-based payment award, range of percentage payout

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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
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-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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- Definition

Description of service or performance condition required to be met for earning right to award under share-based payment arrangement. Includes, but is not limited to, combination of market, performance or service condition.

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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).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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- Definition

Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

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

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No definition available.

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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

Amount of cost expensed and capitalized for award under share-based payment arrangement.

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- Definition

Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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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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Stock-Based Compensation - Narrative (Detail) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	May 31, 2020	Dec. 30, 2023	Dec. 31, 2022	Jan. 01, 2022	Jun. 01, 2017
Schedule Of Share Based Compensation Arrangements [Line Items]
Stock-based compensation expense		$ 7.0	$ 47.7	$ 44.6
Share-based compensation arrangement, weighted average remaining contractual term (in years)		4 years 10 months 24 days	4 years 3 months 18 days
Weighted average remaining contractual term of options exercisable, years		2 years 10 months 24 days	3 years 7 months 6 days
Award vesting rights		three years	three years	three
Total fair market value of all vesting options		$ 9.5	$ 12.4	$ 15.2
Aggregated intrinsic value of options outstanding		123.3
Aggregated intrinsic value of options exercisable		123.3
Aggregated intrinsic value of options exercised		19.0	14.6	84.7
Total income tax benefit recognized for share-based compensation expense		2.9	$ 2.5	$ 16.4
2021 PSU Grant
Schedule Of Share Based Compensation Arrangements [Line Items]
Weighted average shares contingently issuable (in shares)			325,124	138,000
Employee Stock Option
Schedule Of Share Based Compensation Arrangements [Line Items]
Stock-based compensation expense		8.8	$ 11.4	$ 13.0
Unrecognized compensation cost		$ 15.2
Unrecognized share-based compensation related to unvested options granted, term		2 years 3 months 18 days
Restricted Stock Units (RSUs)
Schedule Of Share Based Compensation Arrangements [Line Items]
Stock-based compensation expense		$ 20.1	$ 14.4	$ 9.0
Unrecognized share-based compensation related to unvested options granted		$ 90.7
Weighted average period		4 years
Weighted average shares contingently issuable (in shares)		500,000	300,000	100,000
Performance Shares
Schedule Of Share Based Compensation Arrangements [Line Items]
Stock-based compensation expense		$ (21.9)	$ 21.9	$ 22.6
Unrecognized share-based compensation related to unvested options granted		$ 7.2
Weighted average period		1 year 3 months 18 days
Weighted average shares contingently issuable (in shares)		100,000	300,000	200,000
2017 Equity Incentive Plan
Schedule Of Share Based Compensation Arrangements [Line Items]
Increase in number of shares authorized (in shares)	2,500,000
Maximum \| Performance Shares \| 2021 PSU Grant
Schedule Of Share Based Compensation Arrangements [Line Items]
Weighted average shares contingently issuable (in shares)		103,000	162,562	69,000
Share-based compensation arrangement by share-based payment award, range of percentage payout		200.00%	200.00%	200.00%
Maximum \| 2007 Stock Incentive Plan
Schedule Of Share Based Compensation Arrangements [Line Items]
Number of shares available for grant (in shares)		5,000,000
Maximum \| 2017 Equity Incentive Plan
Schedule Of Share Based Compensation Arrangements [Line Items]
Number of shares available for grant (in shares)	7,500,000
Minimum \| Performance Shares \| 2021 PSU Grant
Schedule Of Share Based Compensation Arrangements [Line Items]
Weighted average shares contingently issuable (in shares)			162,562	69,000
Share-based compensation arrangement by share-based payment award, range of percentage payout		0.00%	0.00%	0.00%
Minimum \| 2017 Equity Incentive Plan
Schedule Of Share Based Compensation Arrangements [Line Items]
Number of shares available for grant (in shares)					5,000,000