ACQUISITIONS (Pro Forma) (Details) - Fusion Packaging - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Unaudited pro forma financial information
Net Sales	$ 759,153	$ 719,008	$ 2,187,974	$ 2,244,834
Net Income Attributable to AptarGroup Inc.	$ 63,724	$ 57,191	$ 160,077	$ 196,195
Net Income per common share — basic	$ 0.99	$ 0.89	$ 2.49	$ 3.09
Net Income per common share — diluted	$ 0.95	$ 0.86	$ 2.41	$ 2.97

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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