Segment Reporting - Narrative (Details) $ in Millions	3 Months Ended
Apr. 03, 2021 USD ($) segment	Apr. 04, 2020 USD ($)
Segment Reporting Information [Line Items]
Reportable operating segments \| segment	2
Restructuring charges	$ 21.7
Seating
Segment Reporting Information [Line Items]
Additional restructuring costs expected to occur	24.0
E-Systems
Segment Reporting Information [Line Items]
Additional restructuring costs expected to occur	15.0
Operating segments \| Seating
Segment Reporting Information [Line Items]
Restructuring charges	12.8	$ 12.3
Operating segments \| E-Systems
Segment Reporting Information [Line Items]
Restructuring charges	4.7	$ 20.3
Other
Segment Reporting Information [Line Items]
Restructuring charges	$ 4.2

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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
-Topic 280
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Amount of expected cost remaining for the specified restructuring cost.

+ References

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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.

+ References

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-Name Accounting Standards Codification
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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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