Earnings Per Share and Equity - Summary of Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2023	Apr. 01, 2022
Earnings Per Share [Abstract]
Net income for basic earnings per share of common stock	$ 461.7	$ 530.2
Add: Interest on 1.625% Notes	0.4	0.5
Net income for diluted earnings per share of common stock	$ 462.1	$ 530.7
Basic weighted average shares of common stock outstanding (in shares)	431.9	433.3
Dilutive effect of share-based awards (in shares)	1.4	2.4
Dilutive effect of convertible notes and warrants (in shares)	15.2	13.2
Diluted weighted-average shares of common stock outstanding (in shares)	448.5	448.9
Net income per share of common stock attributable to ON Semiconductor Corporation:
Basic (in dollars per share)	$ 1.07	$ 1.22
Diluted (in dollars per share)	$ 1.03	$ 1.18