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Business Combination, Working Capital Adjustment

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Number of Reporting Units After Combination

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from estimated impairment losses.

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Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of impairment loss from asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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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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Amount of increase (decrease) of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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Percentage of fair value of reporting unit in excess of carrying amount.

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Goodwill - Narrative (Details) $ in Millions	3 Months Ended				9 Months Ended		12 Months Ended
Goodwill - Narrative (Details) $ in Millions	Sep. 28, 2025 USD ($) reporting_unit	Mar. 30, 2025 USD ($)	Dec. 29, 2024 USD ($)	Sep. 29, 2024 USD ($)	Sep. 28, 2025 USD ($) reporting_unit	Sep. 29, 2024 USD ($)	Dec. 29, 2024 USD ($)	Jun. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)
Goodwill [Line Items]
Goodwill	$ 202.1		$ 304.2		$ 202.1		$ 304.2		$ 151.1
Additions							225.9
Number of reporting units after combination \| reporting_unit	1				1
Goodwill impairment charge	$ 102.0			$ 0.0	$ 102.0	$ 0.0	72.8
Science, Engineering & Technology
Goodwill [Line Items]
Goodwill	$ 137.1		261.4		137.1		261.4		111.3
Additions							222.9
Goodwill impairment charge					$ 102.0		72.8
Reporting unit, percentage of fair value in excess of carrying amount	10.00%				10.00%
Education
Goodwill [Line Items]
Goodwill	$ 42.7		42.8		$ 42.7		42.8		39.8
Additions							3.0
Goodwill impairment charge					0.0		0.0
Enterprise Talent Management
Goodwill [Line Items]
Reallocation					22.3
Goodwill	22.3		0.0		22.3		0.0		$ 0.0
Additions							0.0
Goodwill impairment charge					0.0		0.0
Children's Therapy Center (CTC) \| Education
Goodwill [Line Items]
Goodwill			3.0				$ 3.0
Net working capital adjustment		$ 0.1
Motion Recruitment Partners, LLC
Goodwill [Line Items]
Net working capital adjustment			1.4
Motion Recruitment Partners, LLC \| Science, Engineering & Technology
Goodwill [Line Items]
Goodwill								$ 221.5
Business combination, net working capital liability				$ 1.4
Additions			$ 1.4
Goodwill impairment charge	63.5
Deferred tax assets, tax deferred expense, reserves and accruals, impairment losses	8.6				8.6
Softworld \| Science, Engineering & Technology
Goodwill [Line Items]
Goodwill impairment charge	38.5
Deferred tax assets, tax deferred expense, reserves and accruals, impairment losses	$ 9.8				$ 9.8