Consolidated Statements of Operations and Comprehensive (Loss) Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenues:
Total revenues	$ 1,850,690	$ 2,348,789	$ 2,427,515
Expenses:
Cost of sales	1,369,935	1,500,633	1,435,358
Wholesale selling expenses	50,121	67,103	71,502
Retail operating expenses	387,398	440,395	425,996
Franchise expenses	12,146	13,152	13,214
General and administrative expenses	210,244	177,672	172,764
Art and development costs	17,638	23,203	23,388
Development stage expenses	2,932	10,736	7,008
Gain on sale/leaseback transaction		(58,381)
Store impairment and restructuring charges	22,449	29,038
Loss on assets held for sale	73,948
Goodwill, intangibles and long-lived assets impairment	581,380	562,631
Total expenses	2,728,191	2,766,182	2,149,230
(Loss) income from operations	(877,501)	(417,393)	278,285
Interest expense, net	77,043	114,899	105,706
Other expense, net	3,715	1,871	10,982
(Gain) on debt refinancing	(273,149)
(Loss) income before income taxes	(685,110)	(534,163)	161,597
Income tax expense (benefit)	(156,653)	(1,305)	38,778
Net (loss) income	(528,457)	(532,858)	122,819
Add: Net income attributable to redeemable securities holder			409
Less: Net loss attributable to noncontrolling interests	(219)	(363)	(31)
Net (loss) income attributable to common shareholders of Party City Holdco Inc	$ (528,238)	$ (532,495)	$ 123,259
Net (loss) income per share attributable to common shareholders of Party City Holdco Inc.—Basic	$ (5.24)	$ (5.71)	$ 1.28
Net (loss) income per share attributable to common shareholders of Party City Holdco Inc.—Diluted	$ (5.24)	$ (5.71)	$ 1.27
Weighted-average number of common shares—Basic	100,804,944	93,295,692	96,133,144
Weighted-average number of common shares—Diluted	100,804,944	93,295,692	97,271,050
Other comprehensive (loss) income, net of tax:
Foreign currency adjustments	$ 6,143	$ 12,599	$ (14,479)
Cash flow hedges	(352)	845	1,063
Other comprehensive income (loss), net	5,791	13,444	(13,416)
Comprehensive (loss) income	(522,666)	(519,414)	109,403
Add: Comprehensive income attributable to redeemable securities holder			409
Less: Comprehensive loss attributable to noncontrolling interests	(246)	(386)	(64)
Comprehensive (loss) income attributable to common shareholders of Party City Holdco Inc.	(522,420)	(519,028)	109,876
Net Sales [Member]
Revenues:
Revenues	1,843,444	2,339,510	2,416,442
Royalties and Franchise Fees [Member]
Revenues:
Revenues	$ 7,246	$ 9,279	$ 11,073