Revenue from Contracts with Customers - Summary of Revenue from Contracts with Customers (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Disaggregation of Revenue [Line Items]
Net revenues	$ 535,746	$ 254,691	$ 962,553	$ 668,734
Retail Segment [Member]
Disaggregation of Revenue [Line Items]
Net revenues	443,812	185,782	777,094	488,758
Wholesale Segment [Member]
Disaggregation of Revenue [Line Items]
Net revenues	91,934	68,909	185,459	179,976
Other Retail Segment Store [Member] | Retail Segment [Member]
Disaggregation of Revenue [Line Items]
Net revenues	2,137	4,378	5,374	17,723
Net Sales [Member] | Retail Segment [Member]
Disaggregation of Revenue [Line Items]
Net revenues	443,812	185,782	777,094	488,758
North America [Member] | Party City Stores [Member] | Retail Segment [Member]
Disaggregation of Revenue [Line Items]
Net revenues	441,675	181,404	771,720	471,035
Domestic [Member] | Wholesale Segment [Member]
Disaggregation of Revenue [Line Items]
Net revenues	61,789	39,121	117,146	97,875
International [Member] | Wholesale Segment [Member]
Disaggregation of Revenue [Line Items]
Net revenues	$ 30,145	$ 29,788	$ 68,313	$ 82,101