Earnings Per Share, Reconciliation (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Earnings Per Share
Net income from continuing operations attributable to Amphenol Corporation	$ 418.8	$ 346.6	$ 1,115.5	$ 846.4
Income from discontinued operations attributable to Amphenol Corporation, net of income taxes of ($1.5) and ($1.8) for 2021, respectively	7.7	0.0	10.3	0.0
Income taxes on income from discontinued operations attributable to Amphenol Corporation	1.5		1.8
Net income attributable to Amphenol Corporation	$ 426.5	$ 346.6	$ 1,125.8	$ 846.4
Weighted average common shares outstanding - Basic (in shares)	597.7	597.5	597.8	595.2
Effect of dilutive stock options (in shares)	28.1	18.9	26.8	17.3
Weighted average common shares outstanding - Diluted (in shares)	625.8	616.4	624.6	612.5
Net income (loss) per common share attributable to Amphenol Corporation - Basic:
Continuing operations	$ 0.70	$ 0.58	$ 1.87	$ 1.42
Discontinued operations, net of income taxes	0.01	0	0.02	0
Net income attributable to Amphenol Corporation - Basic	0.71	0.58	1.88	1.42
Net income (loss) per common share attributable to Amphenol Corporation - Diluted:
Continuing operations	0.67	0.56	1.79	1.38
Discontinued operations, net of income taxes	0.01	0	0.02	0
Net income attributable to Amphenol Corporation - Diluted	$ 0.68	$ 0.56	$ 1.80	$ 1.38
Anti-dilutive common shares
Anti-dilutive stock options, excluded from the computations of earnings per share (in shares)	7.4	9.2	3.8	12.2