Selected Quarterly Financial Data (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Selected Quarterly Financial Data (Unaudited)
Net sales	$ 2,151.0	$ 2,100.6	$ 2,015.3	$ 1,958.5	$ 2,224.7	$ 2,129.0	$ 1,981.4	$ 1,866.9	$ 8,225.4	$ 8,202.0	$ 7,011.3
Gross Profit	678.7	661.9	647.6	627.8	715.0	688.2	644.8	606.9	2,616.0	2,654.9	2,309.9
Operating income	429.8	413.6	399.5	376.2	457.6	444.2	408.2	376.9	1,619.2	1,686.9	1,427.6
Net income (loss)	320.8	282.3	290.9	269.9	341.2	319.6	287.8	268.3	1,164.0	1,216.9	660.7
Net income (loss) attributable to Amphenol Corporation shareholders	$ 318.7	$ 280.3	$ 288.4	$ 267.5	$ 338.1	$ 316.6	$ 284.8	$ 265.6	$ 1,155.0	$ 1,205.0	$ 650.5
Net income (loss) per common share - Basic (in dollars per share)	$ 1.07	$ 0.95	$ 0.97	$ 0.90	$ 1.13	$ 1.05	$ 0.95	$ 0.87	$ 3.88	$ 4.00	$ 2.13
Net income (loss) per common share-Diluted (in dollars per share)	$ 1.03	$ 0.92	$ 0.93	$ 0.87	$ 1.09	$ 1.01	$ 0.91	$ 0.84	$ 3.75	$ 3.85	$ 2.06