Consolidated Statements of Stockholders' Deficit - USD ($) $ in Thousands	Common stock	Capital in excess of par value	Accumulated deficit	Accumulated other comprehensive loss	Total
Beginning balance at Dec. 31, 2020	$ 2,126	$ 1,089,199	$ (2,153,368)	$ (96,504)	$ (1,158,547)
Beginning balance (in shares) at Dec. 31, 2020	85,075,901
Increase (Decrease) in Equity (Deficit)
Issuance of common stock	$ 23	13,193			13,216
Issuance of common stock (in shares)	934,206
Stock-based compensation		17,514			17,514
Payment of tax withholdings on equity-based compensation through shares withheld	$ (1)	(2,200)			(2,201)
Payment of tax withholdings on equity-based compensation through shares withheld (in shares)	(49,962)
Employee stock purchase plan	$ 1	647			648
Employee stock purchase plan (in shares)	21,643
Fresh start valuation adjustment for partnership park units purchased			194		194
Net income attributable to Six Flags Entertainment Corporation			131,922		131,922
Net other comprehensive income (loss), net of tax				2,209	2,209
Ending balance at Oct. 03, 2021	$ 2,149	1,118,353	(2,021,252)	(94,295)	(995,045)
Ending balance (in shares) at Oct. 03, 2021	85,981,788
Beginning balance at Jul. 04, 2021	$ 2,147	1,108,680	(2,178,493)	(92,488)	(1,160,154)
Beginning balance (in shares) at Jul. 04, 2021	85,871,956
Increase (Decrease) in Equity (Deficit)
Issuance of common stock	$ 2	1,819			1,821
Issuance of common stock (in shares)	110,370
Stock-based compensation		7,876			7,876
Payment of tax withholdings on equity-based compensation through shares withheld		(22)			(22)
Payment of tax withholdings on equity-based compensation through shares withheld (in shares)	(508)
Employee stock purchase plan (in shares)	(30)
Net income attributable to Six Flags Entertainment Corporation			157,241		157,241
Net other comprehensive income (loss), net of tax				(1,807)	(1,807)
Ending balance at Oct. 03, 2021	$ 2,149	1,118,353	(2,021,252)	(94,295)	(995,045)
Ending balance (in shares) at Oct. 03, 2021	85,981,788
Beginning balance at Jan. 02, 2022	$ 2,154	1,120,084	(2,023,251)	(81,187)	(982,200)
Beginning balance (in shares) at Jan. 02, 2022	86,162,879
Increase (Decrease) in Equity (Deficit)
Issuance of common stock	$ 11	1,028			1,039
Issuance of common stock (in shares)	431,999
Stock-based compensation		9,124			9,124
Repurchase of common stock	$ (87)	(25,394)	(71,293)		(96,774)
Repurchase of common stock (in shares)	(3,464,385)
Payment of tax withholdings on equity-based compensation through shares withheld		(414)			(414)
Payment of tax withholdings on equity-based compensation through shares withheld (in shares)	(9,904)
Employee stock purchase plan	$ 1	625			626
Employee stock purchase plan (in shares)	31,993
Fresh start valuation adjustment for partnership park units purchased			117		117
Net income attributable to Six Flags Entertainment Corporation			95,559		95,559
Net other comprehensive income (loss), net of tax				7,368	7,368
Ending balance at Oct. 02, 2022	$ 2,079	1,105,053	(1,998,868)	(73,819)	(965,555)
Ending balance (in shares) at Oct. 02, 2022	83,152,582
Beginning balance at Jul. 03, 2022	$ 2,075	1,103,534	(2,114,697)	(71,932)	(1,081,020)
Beginning balance (in shares) at Jul. 03, 2022	83,026,556
Increase (Decrease) in Equity (Deficit)
Issuance of common stock	$ 4	(4)
Issuance of common stock (in shares)	128,590
Stock-based compensation		1,676			1,676
Payment of tax withholdings on equity-based compensation through shares withheld		(154)			(154)
Payment of tax withholdings on equity-based compensation through shares withheld (in shares)	(2,564)
Employee stock purchase plan		1			1
Net income attributable to Six Flags Entertainment Corporation			115,829		115,829
Net other comprehensive income (loss), net of tax				(1,887)	(1,887)
Ending balance at Oct. 02, 2022	$ 2,079	$ 1,105,053	$ (1,998,868)	$ (73,819)	$ (965,555)
Ending balance (in shares) at Oct. 02, 2022	83,152,582