Earnings Per Share, Reconciliation (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Earnings Per Share
Net income from continuing operations attributable to Amphenol Corporation	$ 367.2	$ 257.7	$ 696.7	$ 499.8
Income from discontinued operations attributable to Amphenol Corporation, net of income taxes of ($0.3)	2.6	0.0	2.6	0.0
Income taxes on income from discontinued operations attributable to Amphenol Corporation	0.3		0.3
Net income attributable to Amphenol Corporation	$ 369.8	$ 257.7	$ 699.3	$ 499.8
Weighted average common shares outstanding - Basic (in shares)	597.4	593.3	597.9	594.1
Effect of dilutive stock options (in shares)	26.4	14.7	26.0	16.4
Weighted average common shares outstanding - Diluted (in shares)	623.8	608.0	623.9	610.5
Net income (loss) per common share attributable to Amphenol Corporation - Basic:
Continuing operations	$ 0.61	$ 0.43	$ 1.17	$ 0.84
Discontinued operations, net of income taxes	0	0	0	0
Net income attributable to Amphenol Corporation - Basic	0.62	0.43	1.17	0.84
Net income (loss) per common share attributable to Amphenol Corporation - Diluted:
Continuing operations	0.59	0.42	1.12	0.82
Discontinued operations, net of income taxes	0	0	0	0
Net income attributable to Amphenol Corporation - Diluted	$ 0.59	$ 0.42	$ 1.12	$ 0.82
Anti-dilutive common shares
Anti-dilutive stock options, excluded from the computations of earnings per share (in shares)	3.8	27.3	2.2	15.7