Represents the one time self-insured retention for the entity.

No definition available.

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Namespace Prefix:	six_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Insurance coverage provided by the insurance arrangement to the entity.

+ References

No definition available.

+ Details

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Namespace Prefix:	six_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the deductible per occurrence applicable to all claims in the policy year.

+ References

No definition available.

+ Details

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Namespace Prefix:	six_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Excess liability coverage per occurrence provided by the insurance arrangement.

+ References

No definition available.

+ Details

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Namespace Prefix:	six_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	six_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Loss Contingency, Damages Awarded, Percentage Allocated

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the number of claims arising in the period that are expected to have a material adverse effect on the entity's financial condition.

+ References

No definition available.

+ Details

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Namespace Prefix:	six_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the number of individuals who allegedly participated in the altercation.

+ References

No definition available.

+ Details

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Namespace Prefix:	six_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of years plaintiff may reinstate the lawsuit, following the date plaintiff reaches the age of majority

+ References

No definition available.

+ Details

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Namespace Prefix:	six_
Data Type:	xbrli:stringItemType
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- References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of damages awarded to the plaintiff in the legal matter.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14557-108349

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of plaintiffs that have filed claims pertaining to a loss contingency.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Carrying amount (including both current and noncurrent portions) of accrued known and estimated losses incurred as of the balance sheet date for which no insurance coverage exists, and for which a claim has been made or is probable of being asserted, typically arising from workmen's compensation-type of incidents and personal injury to nonemployees from accidents on the entity's property.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.24)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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- Details

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- Details

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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	six_PolicyPeriodAxis=six_November22004December302008Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LossContingenciesByNatureOfContingencyAxis=six_WorkersCompensationPolicyMember
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Data Type:	na
Balance Type:
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- Details

Name:	six_PolicyPeriodAxis=six_November162001November152003Member
Namespace Prefix:
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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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- Details

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Commitments and Contingencies (Details 2)				6 Months Ended
Commitments and Contingencies (Details 2)	Apr. 26, 2016 USD ($)	Oct. 24, 2014 individual	Nov. 20, 2013 USD ($) individual	Jun. 30, 2017 USD ($) claim
Litigation
Number of actions that would be material to consolidated financial position \| claim				0
Multi-layered general liability policies
Insurance
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				500,000.0
Multi-layered general liability policies \| November 16, 2003 - December 30, 2008 [Member]
Insurance
Self-insured retention per occurrence				2,500,000.0
Multi-layered general liability policies \| November 16, 2002 - November 15, 2003 [Member]
Insurance
Self-insured retention per occurrence				2,000,000.0
Multi-layered general liability policies \| November 16, 2001 - November 15, 2002 [Member]
Insurance
Self-insured retention per occurrence				1,000,000.0
Multi-layered general liability policies \| November 2, 2004 - December 30, 2008 [Member]
Insurance
Insurance, Additional Self Insured Retention Value				500,000.0
Workers' compensation claims
Insurance
Deductible per occurrence applicable to all claims in the policy year				750,000.00
Workers' compensation claims \| November 16, 2001 - November 15, 2003 [Member]
Insurance
Deductible per occurrence applicable to all claims in the policy year				500,000.0
Information security and privacy liability insurance policy
Insurance
Self-insured retention per occurrence				250,000.00
Insurance value maintained				10,000,000.0
Personal Injury Due to SFOG Altercation [Member]
Litigation
Numbers of individuals who allegedly participated in the altercation \| individual			4
Loss Contingency, Damages Awarded, Value			$ 35,000,000
Loss Contingency, Damages Awarded, Percentage Allocated			92.00%
Personal Injury Due to SFDK Accident [Member]
Litigation
Loss Contingency, Number of Plaintiffs \| individual		1
Number of years plaintiff may reinstate the lawsuit, following the date plaintiff reaches the age of majority		P2Y
Self insurance reserve				$ 2,500,000
Personal Injury Due to Six Flags Great America Accident [Member]
Litigation
Loss Contingency, Damages Awarded, Value	$ 1,500,000