QUARTERLY DATA (UNAUDITED) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Net Sales	$ 749,329	$ 759,153	$ 699,305	$ 721,553	$ 671,333	$ 701,278	$ 742,661	$ 744,460	$ 2,929,340	$ 2,859,732	$ 2,764,761
Gross profit	231,019	233,988	213,494	227,505	193,588	215,222	231,739	233,841	906,006	874,390
Net income	53,245	63,735	41,860	55,250	48,538	56,769	73,921	62,999	214,090	242,227	194,766
Net income attributable to AptarGroup, Inc.	$ 53,232	$ 63,716	$ 41,839	$ 55,253	$ 48,533	$ 56,750	$ 73,915	$ 63,004	$ 214,040	$ 242,202	$ 194,745
Net Income Attributable to AptarGroup, Inc. per Common Share:
Basic (in dollars per share)	$ 0.82	$ 0.99	$ 0.65	$ 0.86	$ 0.76	$ 0.89	$ 1.16	$ 1.00	$ 3.32	$ 3.81	$ 3.12
Diluted (in dollars per share)	$ 0.79	$ 0.95	$ 0.63	$ 0.84	$ 0.73	$ 0.85	$ 1.12	$ 0.96	$ 3.21	$ 3.66	$ 3.00
Average number of shares outstanding:
Basic (in shares)	64,833	64,562	64,262	64,009	63,835	64,010	63,471	62,964	64,418	63,574	62,437
Diluted (in shares)	67,265	66,922	66,384	66,111	66,192	66,702	66,232	65,349	66,657	66,150	64,958