Name:	amgp_OrganizationConsolidationAndPresentationOfFinancialStatementsLineItems
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Data Type:	xbrli:stringItemType
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Represents the percentage of amount of quarterly distribution in excess of threshold limit.

No definition available.

Name:	amgp_PercentageOfAmountOfQuarterlyDistributionInExcessOfThresholdLimit
Namespace Prefix:	amgp_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Represents the amount of threshold limit for quarterly distribution.

No definition available.

Name:	amgp_ThresholdLimitForQuarterlyDistribution
Namespace Prefix:	amgp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Amount of expense for administrative services provided to the limited liability company (LLC) or limited partnership (LP) by the managing member or general partner, affiliate of managing member or general partner, or affiliate of LLC or LP, for example, but not limited to, salaries, rent, or overhead costs.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Name:	us-gaap_AdministrativeFeesExpense
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

Name:	us-gaap_LimitedLiabilityCompanyLLCOrLimitedPartnershipLPManagingMemberOrGeneralPartnerOwnershipInterest
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Name:	dei_LegalEntityAxis=amgp_AnteroMidstreamPartnersGPLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	dei_LegalEntityAxis=amgp_AnteroIDRHoldingsLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	dei_LegalEntityAxis=amgp_AnteroResourcesCorporationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	dei_LegalEntityAxis=amgp_StonewallGasGatheringLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: