Pre-Production Costs Related to Long-Term Supply Agreements - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Apr. 01, 2023	Apr. 02, 2022
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Capitalized pre-production E&D costs	$ 60.1	$ 63.2
Capitalized pre-production tooling costs related to customer-owned tools	56.3	46.4
Cash collected related to E&D and tooling costs	$ 80.2	$ 72.9

Amount of recoverable preproduction engineering and design costs related to long term supply agreements capitalized during the reporting period.

No definition available.

Name:	lear_PreproductionEngineeringAndDevelopmentCostsRelatedToLongTermSupplyArrangementsCostsCapitalized
Namespace Prefix:	lear_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration