Represents the capital expenditure based on certain percentage of partnership parks revenue.

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Insurance coverage provided by the insurance arrangement to the entity.

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Excess liability coverage per occurrence provided by the insurance arrangement.

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Represents the self-insured retention per occurrence for the entity.

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Line of Credit Facility, Additional Contingent Borrowing Capacity

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Represents the annual distributions by general partners to special partners in Partnership Parks.

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Loss Contingency Number of Claims Consolidated

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Number of questions certified for consideration by appellate court.

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Loss Contingency, Range of Possible Loss Per Aggrieved Party

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Represents the rolling period for making minimum capital expenditure at each of the Partnership Parks.

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No definition available.

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Represents the share of the entity in annual distributions to be made by the general partners of the partnership parks.

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

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Represents the period of Weighted average EBITDA used for deriving the value of the purchase price.

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

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Represents the threshold purchase price of partnership parks.

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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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Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The total number of new claims filed pertaining to a loss contingency during the period.

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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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Redemption value, as if currently redeemable, of redeemable noncontrolling interest classified as temporary equity and the election has been made to accrete changes in redemption value to the earliest redemption date.

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Commitments and Contingencies (Details)				1 Months Ended				3 Months Ended		12 Months Ended
Commitments and Contingencies (Details)	Mar. 02, 2020 claim	Jan. 07, 2016 USD ($)	Apr. 01, 1998 USD ($)	May 31, 2020 USD ($)	Apr. 30, 2020 claim	Apr. 08, 2020 claim	Feb. 29, 2020 claim	Mar. 31, 2020 USD ($) multiple	Mar. 31, 2019 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2017 USD ($) claim	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	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														$ 529,300,000
Additions to property and equipment								$ 53,458,000	$ 48,083,000
Total loans receivable from the partnerships that own partnership parks													$ 239,300,000
Range of possible loss per aggrieved party		$ 1,000
Number of questions certified for consideration by appellate court \| item															2
Number of claims filed \| claim					2	3	2					4
Number of claims consolidated \| claim	2
Minimum
Details of commitments and contingencies
Range of possible loss per aggrieved party												$ 100
Maximum
Details of commitments and contingencies
Range of possible loss per aggrieved party		$ 5,000										$ 1,000
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
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)								31.00%
Remaining redeemable units (as a percent)								69.00%
Six Flags over Texas
Details of commitments and contingencies
Limited partner interests owned (as a percent)								53.20%
Remaining redeemable units (as a percent)								46.80%
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											$ 21,100,000
Cash generated from operating activities by partnerships, after deduction of capital expenditures and excluding the impact of short-term intercompany advances											$ 79,900,000
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
Scenario, Forecast \| Six Flags over Georgia
Details of commitments and contingencies
Units to be purchased in partnership parks				$ 1,500,000
Scenario, Forecast \| Six Flags over Texas
Details of commitments and contingencies
Units to be purchased in partnership parks				$ 3,500,000
Scenario, Forecast \| Six Flags over Texas and Georgia
Details of commitments and contingencies
Annual distributions by general partners to limited partners in partnership parks										$ 74,200,000
Share of Partnership Parks' annual distributions paid to Six Flags Entertainment Corporation										32,500,000
Additions to property and equipment										$ 15,000,000.0