| Document and Entity Information | Oct. 15, 2020 |
| Cover [Abstract] | |
| Amendment Flag | false |
| Entity Central Index Key | 0001592058 |
| Document Type | 8-K |
| Document Period End Date | Oct. 15, 2020 |
| Entity Registrant Name | PARTY CITY HOLDCO INC. |
| Entity Incorporation State Country Code | DE |
| Entity File Number | 001-37344 |
| Entity Tax Identification Number | 46-0539758 |
| Entity Address, Address Line One | 80 Grasslands Road |
| Entity Address, City or Town | Elmsford |
| Entity Address, State or Province | NY |
| Entity Address, Postal Zip Code | 10523 |
| City Area Code | (914) |
| Local Phone Number | 345-2020 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Common Stock, Par Value: $0.01/share |
| Trading Symbol | PRTY |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
