Condensed Consolidated Statement of Stockholders' Equity - 6 months ended Jun. 30, 2018 - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [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, 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 (see Note 2)	(78)			(78)		(78)		(78)
Balance, as adjusted at Dec. 31, 2017	968,712	1,198	917,192	372,518	(35,818)	1,255,090	(286,733)	968,357	355
Net income	26,885			26,944		26,944		26,944	(59)
Net income attributable to redeemable securities holder	410			410		410		410
Stock option expense	942		942			942		942
Restricted stock units - time-based	252		252			252		252
Restricted stock units - performance-based	593		593			593		593
Director - non-cash compensation	59		59			59		59
Warrant expense	326		326			326		326
Exercise of stock options	482	1	481			482		482
Foreign currency adjustments	(5,321)				(5,307)	(5,307)		(5,307)	(14)
Impact of foreign exchange contracts, net	1,328				1,328	1,328		1,328
Balance at Jun. 30, 2018	$ 994,668	$ 1,199	$ 919,845	$ 399,872	$ (39,797)	$ 1,281,119	$ (286,733)	$ 994,386	$ 282