Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Quarterly Financial Data
Net sales	$ 891.7	$ 894.6	$ 803.5	$ 923.4	$ 896.2	$ 914.0	$ 1,000.0	$ 979.7	$ 3,513.2	$ 3,789.9	$ 3,580.8
Gross profit	237.0	263.7	230.3	278.9	256.0	277.5	305.7	302.6	1,009.9	1,141.8	1,040.1
Selling, general and administrative expenses	135.7	132.7	111.8	153.6	159.2	148.0	158.7	152.7	533.8	618.6	580.7
Impairment and restructuring charges	2.5	12.0	3.1	3.6	3.3	1.6	1.9	0.0	21.2	6.8	4.9
Net Income	55.3	91.3	61.8	84.0	117.8	66.7	94.9	95.3	292.4	374.7	305.5
Net income attributable to noncontrolling interests	2.2	2.5	(0.1)	3.3	4.3	2.5	2.4	3.4	7.9	12.6	2.7
Net income attributable to The Timken Company	$ 53.1	$ 88.8	$ 61.9	$ 80.7	$ 113.5	$ 64.2	$ 92.5	$ 91.9	$ 284.5	$ 362.1	$ 302.8
Net income per share - Basic (in dollars per share)	$ 0.70	$ 1.18	$ 0.82	$ 1.07	$ 1.51	$ 0.85	$ 1.22	$ 1.21	$ 3.78	$ 4.78	$ 3.93
Net income per share - Diluted (in dollars per share)	0.69	1.16	0.82	1.06	1.48	0.84	1.20	1.19	3.72	4.71	$ 3.86
Dividends per share (in dollars per share)	$ 0.29	$ 0.28	$ 0.28	$ 0.28	$ 0.28	$ 0.28	$ 0.28	$ 0.28	$ 1.13	$ 1.12
Recognition of net actuarial (gains) losses	$ 21.6	$ 11.9	$ 8.8		$ 21.1	$ 16.9			$ 18.5	$ (4.1)	$ 12.8
Valuation allowance changes									$ 0.7	$ 44.5	$ 0.0