Condensed Consolidated Statements of Comprehensive Income (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 28, 2014	Jun. 29, 2013	Jun. 28, 2014	Jun. 29, 2013
Income Statement [Abstract]
Net sales	$ 4,585.1	$ 4,113.1	$ 8,944.9	$ 8,060.2
Cost of sales	4,206.0	3,775.4	8,205.3	7,410.1
Selling, general and administrative expenses	138.0	127.9	274.7	257.5
Amortization of intangible assets	8.3	8.6	16.8	17.2
Interest expense	14.6	17.4	31.4	34.1
Other expense, net	16.8	10.3	46.0	21.0
Consolidated income before provision for income taxes and equity in net income of affiliates	201.4	173.5	370.7	320.3
Provision for income taxes	52.8	41.1	105.5	79.0
Equity in net income of affiliates	(9.2)	(9.9)	(21.2)	(17.9)
Consolidated net income	157.8	142.3	286.4	259.2
Less: Net income attributable to noncontrolling interests	9.3	5.0	15.9	13.4
Net income attributable to Lear	148.5	137.3	270.5	245.8
Basic net income per share attributable to Lear	$ 1.84	$ 1.62	$ 3.34	$ 2.74
Diluted net income per share attributable to Lear	$ 1.81	$ 1.60	$ 3.28	$ 2.71
Average common shares outstanding	80,920,465	84,517,205	80,996,837	89,609,759
Average diluted shares outstanding	81,940,772	85,550,974	82,344,306	90,653,705
Consolidated comprehensive income (Note 12)	163.5	113.7	281.3	208.4
Less: Comprehensive income attributable to noncontrolling interests	9.0	5.3	13.8	14.1
Comprehensive income attributable to Lear	$ 154.5	$ 108.4	$ 267.5	$ 194.3