Reporting Segments and Related Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended										12 Months Ended
	Dec. 31, 2014		Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013		Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Segment Reporting Information [Line Items]
Customer sales											$ 8,305.1		$ 7,436.6		$ 7,183.2
Net sales	1,991.9		2,032.1	2,197.0	2,084.1	1,885.4		1,806.2	1,893.9	1,851.1	8,305.1		7,436.6		7,183.2
Year-end assets	7,228.0					6,917.0					7,228.0		6,917.0		6,400.8
Depreciation and amortization											330.4		299.4		288.6
Long-lived asset expenditures											563.0	[1]	417.8	[1]	407.4	[1]
Operating Segments [Member]
Segment Reporting Information [Line Items]
Customer sales											8,305.1		7,436.6		7,183.2
Net sales											8,305.1		7,436.6		7,183.2
Year-end assets	5,719.7					5,305.7					5,719.7		5,305.7		4,951.4
Depreciation and amortization											308.1		279.6		269.1
Long-lived asset expenditures											539.0	[1]	400.4	[1]	395.5	[1]
Engine [Member]
Segment Reporting Information [Line Items]
Customer sales											5,673.7		4,990.1		4,884.5
Inter-segment sales											32.2		32.0		28.5
Net sales											5,705.9		5,022.1		4,913.0
Year-end assets	3,936.2					3,519.1					3,936.2		3,519.1		3,299.2
Depreciation and amortization											215.3		189.1		177.8
Long-lived asset expenditures											349.8	[1]	277.5	[1]	269.9	[1]
Drivetrain [Member]
Segment Reporting Information [Line Items]
Customer sales											2,631.4		2,446.5		2,298.7
Inter-segment sales
Net sales											2,631.4		2,446.5		2,298.7
Year-end assets	1,783.5					1,786.6					1,783.5		1,786.6		1,652.2
Depreciation and amortization											92.8		90.5		91.3
Long-lived asset expenditures											189.2	[1]	122.9	[1]	125.6	[1]
Inter-segment eliminations [Member]
Segment Reporting Information [Line Items]
Inter-segment sales											(32.2)		(32.0)		(28.5)
Net sales											(32.2)		(32.0)		(28.5)
Corporate Segment [Member]
Segment Reporting Information [Line Items]
Year-end assets	1,508.3	[2]				1,611.3	[2]				1,508.3	[2]	1,611.3	[2]	1,449.4	[2]
Depreciation and amortization											22.3	[2]	19.8	[2]	19.5	[2]
Long-lived asset expenditures											$ 24.0	[1],[2]	$ 17.4	[1],[2]	$ 11.9	[1],[2]

[1] Long-lived asset expenditures include capital expenditures and tooling outlays.

[2] Corporate assets include investments and other long-term receivables and deferred income taxes.