ACQUISITIONS (Pro Forma) (Details) - CSP Technologies - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2018
Unaudited pro forma financial information
Net Sales	$ 687,201	$ 2,172,737
Net Income Attributable to AptarGroup, Inc.	$ 48,034	$ 158,527
Net Income per common share - basic	$ 0.77	$ 2.54
Net Income per common share - diluted	$ 0.74	$ 2.45

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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