Recent Accounting Changes and Pronouncements - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Other income (expense) – net	$ (2.7)	$ 2.1
Engineering, selling, and administrative expense	(60.4)	(61.4)
Operating cash flows	173.0	109.3
Investing cash flows	148.5	$ 74.7
Accounting Standards Update 2017-07
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Other income (expense) – net	1.9
Engineering, selling, and administrative expense	1.9
Accounting Standards Update 2016-15
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Operating cash flows	76.8
Investing cash flows	$ 76.8