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The net cash from (used in) the partnership parks' continuing operations.

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The specified multiple for each of the partnership parks for calculation and valuation of purchase prices.

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For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

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Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

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Change in the different classes of partners' capital accounts during the year due to acquisitions. Partners include general, limited and preferred partners.

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Commitments and Contingencies (Details)						1 Months Ended			3 Months Ended		12 Months Ended
Commitments and Contingencies (Details)	Dec. 03, 2020 lawsuit	Apr. 21, 2020 claim	Apr. 08, 2020 claim	Jan. 07, 2016 USD ($)	Apr. 01, 1998 USD ($)	May 30, 2021 USD ($)	Apr. 30, 2020 lawsuit	Feb. 29, 2020 claim	Apr. 04, 2021 USD ($) multiple	Mar. 31, 2020 USD ($)	Jan. 02, 2022 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2017 USD ($) lawsuit	Apr. 07, 2017 item
Details of commitments and contingencies
Acquisition of capital stock of the former Six Flags Entertainment Corporation, paid in cash					$ 976,000,000.0
Redemption value of noncontrolling interests									$ 523,400,000
Additions to property and equipment									23,133,000	$ 53,458,000
Privacy Class Action Lawsuits \| Pending Litigation
Details of commitments and contingencies
Number of claims filed \| lawsuit													4
Number of lawsuits stayed pending final approval of settlement \| lawsuit	4
Privacy Class Action Lawsuits \| Pending Litigation \| Minimum
Details of commitments and contingencies
Range of possible loss per aggrieved party													$ 100
Privacy Class Action Lawsuits \| Pending Litigation \| Maximum
Details of commitments and contingencies
Range of possible loss per aggrieved party													$ 1,000
Securities Class Action Lawsuits \| Pending Litigation
Details of commitments and contingencies
Number of claims filed \| claim								2
Stockholder Derivative Lawsuits \| Pending Litigation
Details of commitments and contingencies
Number of claims filed \| lawsuit							2
Number of claims consolidated \| claim			3
COVID-19 Park Closure Lawsuits \| Pending Litigation
Details of commitments and contingencies
Number of claims filed \| claim		3
BIPA \| Privacy Class Action Lawsuits \| Pending Litigation
Details of commitments and contingencies
Number of questions certified for consideration by appellate court \| item														2
BIPA \| Privacy Class Action Lawsuits \| Pending Litigation \| Minimum
Details of commitments and contingencies
Range of possible loss per aggrieved party				$ 1,000
BIPA \| Privacy Class Action Lawsuits \| Pending Litigation \| Maximum
Details of commitments and contingencies
Range of possible loss per aggrieved party				$ 5,000
Multi-layered general liability policies
Details of commitments and contingencies
Excess liability coverage per occurrence									100,000,000.0
Self-insured retention per occurrence									2,000,000.0
Deductible per occurrence applicable to all claims in the policy year									500,000
Workers' compensation claims
Details of commitments and contingencies
Deductible per occurrence applicable to all claims in the policy year									750,000
Workers' compensation claims \| November 16, 2001 - November 15, 2003
Details of commitments and contingencies
Deductible per occurrence applicable to all claims in the policy year									500,000
Information security and privacy liability insurance policy
Details of commitments and contingencies
Self-insured retention per occurrence									250,000
Insurance value maintained									10,000,000.0
Partnerships That Own Partnership Parks
Details of commitments and contingencies
Total loans receivable									288,300,000	$ 239,300,000		$ 288,300,000
Amended And Restated Term Loan B As Amended June 2017
Details of commitments and contingencies
Additional contingent borrowing capacity									$ 350,000,000.0
Six Flags over Georgia
Details of commitments and contingencies
Limited partner interests owned (as a percent)									31.40%
Remaining redeemable units (as a percent)									68.60%
Six Flags over Texas
Details of commitments and contingencies
Limited partner interests owned (as a percent)									53.90%
Remaining redeemable units (as a percent)									46.10%
Six Flags over Texas and Georgia
Details of commitments and contingencies
Rolling period for making minimum capital expenditure at each of the Partnership Parks									5 years
Percentage of capital expenditures to Partnership Parks' revenues									6.00%
Weighted average period of the park's EBITDA for calculation of value of purchase price									4 years
Additions to property and equipment												9,100,000
Cash generated from operating activities by partnerships, after deduction of capital expenditures and excluding the impact of short-term intercompany advances												$ 5,000,000.0
Six Flags over Georgia
Details of commitments and contingencies
Specified multiple for purchase price valuation (in multipliers) \| multiple									8.0
Specified price for purchase of partnership parks									$ 409,700,000
Six Flags over Texas
Details of commitments and contingencies
Specified multiple for purchase price valuation (in multipliers) \| multiple									8.5
Specified price for purchase of partnership parks									$ 527,400,000
Forecast \| Six Flags over Georgia
Details of commitments and contingencies
Purchase price of partnership units						$ 1,000,000.0
Forecast \| Six Flags over Texas and Georgia
Details of commitments and contingencies
Annual distributions by general partners to limited partners in partnership parks											$ 75,200,000
Share of Partnership Parks' annual distributions paid to Six Flags Entertainment Corporation											33,300,000
Additions to property and equipment											$ 11,000,000.0
Forecast \| Six Flags over Texas
Details of commitments and contingencies
Purchase price of partnership units						$ 1,200,000