Fair Value Measurements - Summary of Carrying Amount and Fair Value (Detail) $ in Thousands	Jun. 30, 2021 USD ($)
Debt Instrument [Line Items]
Debt Instrument Carrying Amount	$ 1,380,591
8.75% Senior Secured First Lien Notes - due 2026 [Member] | Senior Secured First Lien Notes [Member]
Debt Instrument [Line Items]
Debt Instrument Carrying Amount	750,000
Debt Instrument Fair Value	802,500
6.125% Senior Notes - due 2023 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument Carrying Amount	22,924
Debt Instrument Fair Value	20,202
6.625% Senior Notes - due 2026 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument Carrying Amount	92,254
Debt Instrument Fair Value	78,762
First Lien Party City Notes - due 2025 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument Carrying Amount	202,588
Debt Instrument Fair Value	193,725
First Lien Anagram Notes - due 2025 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument Carrying Amount	151,313
Debt Instrument Fair Value	173,632
Second Lien Anagram Notes - due 2026 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument Carrying Amount	148,114
Debt Instrument Fair Value	$ 148,114