Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Statement [Abstract]
Net sales	$ 358.5	$ 340.2	$ 1,068.1	$ 934.8
Cost of sales	318.4	290.5	936.1	817.0
Gross profit	40.1	49.7	132.0	117.8
Selling, general and administrative expenses	45.1	38.7	128.1	114.7
Operating (loss) income	(5.0)	11.0	3.9	3.1
Other components of pension income and other postretirement benefits expense, net	2.4	1.9	7.3	5.5
Interest expense, net	(7.6)	(7.4)	(22.4)	(22.9)
(Loss) income before income taxes	(10.2)	5.5	(11.2)	(14.3)
Income tax benefit (expense)	2.8	(0.3)	3.7	3.8
Net (loss) income	(7.4)	5.2	(7.5)	(10.5)
Net loss attributable to noncontrolling interests	0.2	0.1	0.5	0.4
Net (loss) income attributable to Park-Ohio Holdings Corp. common shareholders	$ (7.2)	$ 5.3	$ (7.0)	$ (10.1)
(Loss) income per common share attributable to Park-Ohio Holdings Corp. common shareholders:
Basic (in dollars per share)	$ (0.60)	$ 0.44	$ (0.58)	$ (0.83)
Diluted (in dollars per share)	$ (0.60)	$ 0.44	$ (0.58)	$ (0.83)
Weighted-average shares used to compute (loss) income per share:
Basic (in shares)	12.1	12.0	12.0	12.1
Diluted (in shares)	12.1	12.0	12.0	12.1