Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings (Deficit) [Member]	Accumulated Other Comprehensive Loss [Member]	Total Party City Holdco Inc. Stockholders' Equity Before Common Stock Held In Treasury [Member]	Common Stock Held In Treasury [Member]	Total Party City Holdco Inc. Stockholders' Equity [Member]	Non-Controlling Interests [Member]
Balance at Dec. 31, 2016	$ 1,016,789	$ 1,195	$ 910,167	$ 157,666	$ (52,239)	$ 1,016,789		$ 1,016,789
Balance, adjusted at Dec. 31, 2016	968,712	1,198	917,192	372,518	(35,818)	1,255,090	$ (286,733)	968,357	$ 355
Net income (loss)	215,340			215,340		215,340		215,340
Stock option expense	5,309		5,309			5,309		5,309
Warrant	421		421			421		421
Adjustment to redeemable securities	(410)			(410)		(410)		(410)
Exercise of stock options	1,298	3	1,295			1,298		1,298
Acquired noncontrolling interest	355							0	355
Foreign currency adjustments	17,561				17,561	17,561		17,561
Treasury stock purchases	(286,733)						(286,733)	(286,733)
Impact of foreign exchange contracts	(1,140)				(1,140)	(1,140)		(1,140)
Balance at Dec. 31, 2017	968,790	1,198	917,192	372,596	(35,818)	1,255,168	(286,733)	968,435	355
Cumulative effect of change in accounting principle, net	(78)			(78)		(78)		(78)
Balance, adjusted at Dec. 31, 2017	1,043,780	1,208	923,138	495,274	(49,201)	1,370,419	(326,930)	1,043,489	291
Net income (loss)	122,819			122,850		122,850		122,850	(31)
Net income attributable to redeemable securities holder	409			409		409		409
Stock option expense	1,744		1,744			1,744		1,744
Restricted stock units — time-based	1,174	6	1,168			1,174		1,174
Directors — non-cash compensation	196		196			196		196
Warrant	(89)		(89)			(89)		(89)
Exercise of stock options	2,269	4	2,265			2,269		2,269
Foreign currency adjustments	(14,479)				(14,446)	(14,446)		(14,446)	(33)
Treasury stock purchases	(40,197)						(40,197)	(40,197)
Impact of foreign exchange contracts	1,063				1,063	1,063		1,063
Balance at Dec. 31, 2018	1,043,621	1,208	922,476	495,777	(49,201)	1,370,260	(326,930)	1,043,330	291
Cumulative effect of change in accounting principle, net	159		662	(503)		159		159
Net income (loss)	(532,858)			(532,495)		(532,495)		(532,495)	(363)
Stock option expense	1,319		1,319			1,319		1,319
Restricted stock units — time-based	2,033		2,033			2,033		2,033
Directors — non-cash compensation	313		313			313		313
Warrant	515		515			515		515
Exercise of stock options	1,148	3	1,145			1,148		1,148
Acquired noncontrolling interest	181		110			110		110	71
Foreign currency adjustments	12,599				12,622	12,622		12,622	(23)
Treasury stock purchases	(156)						(156)	(156)
Impact of foreign exchange contracts	847			2	845	847		847
Balance at Dec. 31, 2019	$ 529,721	$ 1,211	$ 928,573	$ (37,219)	$ (35,734)	$ 856,831	$ (327,086)	$ 529,745	$ (24)