Leases - Additional Information (Details) $ in Millions	9 Months Ended
Sep. 30, 2020 USD ($)
Leases
Option to terminate, term	1 year
Total estimated future lease payments	$ 2.2
Minimum
Leases
Term of contract	1 year
Maximum
Leases
Term of contract	45 years
Renewal term	20 years

Amount of lessee's undiscounted obligation for lease payments for finance and operating leases.

No definition available.

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Balance Type:	credit
Period Type:	instant

- Definition

Lessee, Operating Lease, Option to Terminate, Term

+ References

No definition available.

+ Details

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Namespace Prefix:	six_
Data Type:	xbrli:durationItemType
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Period Type:	duration

- Definition

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.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918673-209980

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

+ Details

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Balance Type:	na
Period Type:	instant

- Details

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- Details

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