Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 10.2	$ 10.1
Other comprehensive income, net of tax:
Currency translation and related hedging instruments	4.2	3.9
Pension and other postretirement benefits	1.3	0.2
Total other comprehensive income	5.5	4.1
Total comprehensive income, net of tax	15.7	14.2
Comprehensive income attributable to noncontrolling interests	(0.4)	(0.3)
Comprehensive income attributable to Park-Ohio Holdings Corp. common shareholders	$ 15.3	$ 13.9