Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 03, 2021	Sep. 30, 2020	Oct. 03, 2021	Sep. 30, 2020
Total revenues	$ 638,284	$ 126,327	$ 1,180,095	$ 247,973
Operating expenses (excluding depreciation and amortization shown separately below)	228,119	113,833	504,530	282,378
Selling, general and administrative expenses	64,356	41,568	150,687	114,578
Costs of products sold	54,100	12,980	100,509	22,954
Other net periodic pension benefit	(76)	(995)	(3,409)	(2,985)
Depreciation	28,047	28,780	84,921	87,875
Amortization	6	5	17	1,008
Loss on disposal of assets	624	10,065	1,863	10,458
Interest expense	38,224	38,500	114,797	117,234
Interest income	(129)	(108)	(234)	(638)
Loss on debt extinguishment				6,106
Other expense, net	346	13,470	8,796	19,282
Income (loss) before income taxes	224,667	(131,771)	217,618	(410,277)
Income tax expense (benefit)	46,543	(36,243)	43,930	(113,953)
Net income (loss)	178,124	(95,528)	173,688	(296,324)
Less: Net income attributable to noncontrolling interests	(20,883)	(20,644)	(41,766)	(41,288)
Net income (loss) attributable to Six Flags Entertainment Corporation	$ 157,241	$ (116,172)	$ 131,922	$ (337,612)
Weighted-average common shares outstanding:
Weighted-average common shares outstanding-basic (in shares)	85,919	84,829	85,596	84,730
Weighted-average common shares outstanding - diluted (in shares)	87,259	84,829	87,078	84,730
Earnings (loss) per average common share outstanding:
Earnings (loss) per average common share outstanding - Basic (in dollars per share)	$ 1.83	$ (1.37)	$ 1.54	$ (3.98)
Earnings (loss) per average common share outstanding - Diluted (in dollars per share)	$ 1.80	$ (1.37)	$ 1.51	(3.98)
Cash dividends declared per common share				$ 0.25
Park admissions
Total revenues	$ 345,217	$ 72,920	$ 634,716	$ 143,688
Park food, merchandise and other
Total revenues	280,499	49,342	510,620	83,671
Sponsorship international agreements and accommodations
Total revenues	$ 12,568	$ 4,065	$ 34,759	$ 20,614