| Cover | Feb. 02, 2021 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Feb. 2, 2021 |
| Entity Registrant Name | AMCOR PLC |
| Entity Incorporation, State or Country Code | Y9 |
| Entity File Number | 001-38932 |
| Entity Tax Identification Number | 98-1455367 |
| Entity Address, Address Line One | 83 Tower Road North |
| Entity Address, City or Town | Warmley, Bristol |
| Entity Address, Country | GB |
| Entity Address, Postal Zip Code | BS30 8XP |
| Country Region | 44 |
| City Area Code | 117 |
| Local Phone Number | 9753200 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Listings [Line Items] | |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0001748790 |
| Amendment Flag | false |
| Ordinary Shares, par value $0.01 per share | |
| Entity Listings [Line Items] | |
| Title of 12(b) Security | Ordinary Shares, par value $0.01 per share |
| Trading Symbol | AMCR |
| Security Exchange Name | NYSE |
| 1.125% Guaranteed Senior Notes Due 2027 | |
| Entity Listings [Line Items] | |
| Title of 12(b) Security | 1.125% Guaranteed Senior Notes Due 2027 |
| Trading Symbol | AUKF/27 |
| Security Exchange Name | NYSE |
