Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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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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Segment Reporting - Narrative (Details) $ in Millions	3 Months Ended		9 Months Ended
Segment Reporting - Narrative (Details) $ in Millions	Oct. 02, 2021 USD ($)	Oct. 03, 2020 USD ($)	Oct. 02, 2021 USD ($) segment	Oct. 03, 2020 USD ($)
Segment Reporting Information [Line Items]
Reportable operating segments \| segment			2
Restructuring charges			$ 78.0
Seating
Segment Reporting Information [Line Items]
Additional restructuring costs expected to occur	$ 18.0		18.0
E-Systems
Segment Reporting Information [Line Items]
Additional restructuring costs expected to occur	19.0		19.0
Operating segments \| Seating
Segment Reporting Information [Line Items]
Restructuring charges	15.2	$ 33.6	35.2	$ 59.3
Operating segments \| E-Systems
Segment Reporting Information [Line Items]
Restructuring charges	28.9	5.0	37.3	46.2
Other
Segment Reporting Information [Line Items]
Restructuring charges	$ 1.3	$ 0.3	$ 5.5	$ 0.9