v2.4.1.9

Long-term Debt (Details) (USD $) | 0 Months Ended | 12 Months Ended
--- | --- | ---
Nov. 10, 2014 | Dec. 31, 2014
Line of credit | Gathering and compression assets |  |
Long-term debt |  |
Outstanding balance | 510,000,000 us-gaap_LineOfCredit / us-gaap_CreditFacilityAxis = us-gaap_LineOfCreditMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = am_GatheringAndCompressionAssetsMember |
Line of credit | Minimum | Predecessor |  |
Long-term debt |  |
Commitment fees on the unused portion (as a percent) |  | 0.375%us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage / us-gaap_CreditFacilityAxis = us-gaap_LineOfCreditMember / us-gaap_RangeAxis = us-gaap_MinimumMember / us-gaap_StatementScenarioAxis = us-gaap_PredecessorMember
Line of credit | Minimum | LIBOR | Predecessor |  |
Long-term debt |  |
Basis spread on variable rate (as a percent) |  | 1.50%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_CreditFacilityAxis = us-gaap_LineOfCreditMember / us-gaap_RangeAxis = us-gaap_MinimumMember / us-gaap_StatementScenarioAxis = us-gaap_PredecessorMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember
Line of credit | Minimum | Prime rate | Predecessor |  |
Long-term debt |  |
Basis spread on variable rate (as a percent) |  | 0.50%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_CreditFacilityAxis = us-gaap_LineOfCreditMember / us-gaap_RangeAxis = us-gaap_MinimumMember / us-gaap_StatementScenarioAxis = us-gaap_PredecessorMember / us-gaap_VariableRateAxis = us-gaap_PrimeRateMember
Line of credit | Maximum | Predecessor |  |
Long-term debt |  |
Commitment fees on the unused portion (as a percent) |  | 0.50%us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage / us-gaap_CreditFacilityAxis = us-gaap_LineOfCreditMember / us-gaap_RangeAxis = us-gaap_MaximumMember / us-gaap_StatementScenarioAxis = us-gaap_PredecessorMember
Line of credit | Maximum | LIBOR | Predecessor |  |
Long-term debt |  |
Basis spread on variable rate (as a percent) |  | 2.50%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_CreditFacilityAxis = us-gaap_LineOfCreditMember / us-gaap_RangeAxis = us-gaap_MaximumMember / us-gaap_StatementScenarioAxis = us-gaap_PredecessorMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember
Line of credit | Maximum | Prime rate | Predecessor |  |
Long-term debt |  |
Basis spread on variable rate (as a percent) |  | 1.50%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_CreditFacilityAxis = us-gaap_LineOfCreditMember / us-gaap_RangeAxis = us-gaap_MaximumMember / us-gaap_StatementScenarioAxis = us-gaap_PredecessorMember / us-gaap_VariableRateAxis = us-gaap_PrimeRateMember
New revolving credit facility |  |
Long-term debt |  |
Maximum amount of the Credit Facility |  | 1,000,000,000 us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember
Interest coverage ratio | 2.5 am_DebtInstrumentCovenantInterestCoverageRatio / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember |
Consolidated total leverage ratio | 5.0 am_DebtInstrumentCovenantLeverageRatio / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember |
Consolidated total leverage ratio after electing to issue high yield notes | 5.25 am_DebtInstrumentCovenantLeverageRatioAfterElectingToIssueNotes / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember |
Period of fiscal quarter after a material acquisition considered in leverage ratio | 2 am_DebtInstrumentCovenantPeriodOfQuarterAfterMaterialAcquisitionConsideredInLeverageRatio / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember |
Consolidated total leverage ratio after a material acquisition | 5.50 am_DebtInstrumentCovenantLeverageRatioAfterMaterialAcquisition / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember |
Consolidated senior secured leverage ratio | 3.75 am_DebtInstrumentCovenantSeniorSecuredLeverageRatio / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember |
New revolving credit facility | LIBOR | Base rate loans |  |
Long-term debt |  |
Description of variable rate basis |  | LIBOR
New revolving credit facility | Reference rate | Base rate loans |  |
Long-term debt |  |
Description of variable rate basis |  | the agent bank's reference rate
New revolving credit facility | Federal funds effective rate | Base rate loans |  |
Long-term debt |  |
Description of variable rate basis |  | the federal funds effective rate
Basis spread on variable rate (as a percent) | 0.50%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_DebtInstrumentAxis = am_BaseRateLoansMember / us-gaap_VariableRateAxis = us-gaap_FederalFundsEffectiveSwapRateMember |
New revolving credit facility | One month Eurodollar rate | Base rate loans |  |
Long-term debt |  |
Description of variable rate basis |  | one month Eurodollar
Basis spread on variable rate (as a percent) | 1.00%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_DebtInstrumentAxis = am_BaseRateLoansMember / us-gaap_VariableRateAxis = us-gaap_EurodollarMember |
New revolving credit facility | Minimum | LIBOR | Eurodollar loans |  |
Long-term debt |  |
Basis spread on variable rate (as a percent) | 1.50%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_DebtInstrumentAxis = am_EurodollarLoansMember / us-gaap_RangeAxis = us-gaap_MinimumMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember |
New revolving credit facility | Minimum | One month Eurodollar rate | Base rate loans |  |
Long-term debt |  |
Additional spread on variable rate (as a percent) | 0.50%am_DebtInstrumentAdditionalSpreadOnVariableRate / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_DebtInstrumentAxis = am_BaseRateLoansMember / us-gaap_RangeAxis = us-gaap_MinimumMember / us-gaap_VariableRateAxis = us-gaap_EurodollarMember |
New revolving credit facility | Maximum | LIBOR | Eurodollar loans |  |
Long-term debt |  |
Basis spread on variable rate (as a percent) | 2.25%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_DebtInstrumentAxis = am_EurodollarLoansMember / us-gaap_RangeAxis = us-gaap_MaximumMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember |
New revolving credit facility | Maximum | One month Eurodollar rate | Base rate loans |  |
Long-term debt |  |
Additional spread on variable rate (as a percent) | 1.25%am_DebtInstrumentAdditionalSpreadOnVariableRate / us-gaap_CreditFacilityAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_DebtInstrumentAxis = am_BaseRateLoansMember / us-gaap_RangeAxis = us-gaap_MaximumMember / us-gaap_VariableRateAxis = us-gaap_EurodollarMember |
Letter of credit |  |
Long-term debt |  |
Current borrowing capacity |  | 150,000,000 us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity / us-gaap_CreditFacilityAxis = us-gaap_LetterOfCreditMember

X
- Definition Additional percentage points added to the reference rate to compute the variable rate on the debt instrument. + References No definition available. + Details
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- Definition Represents the minimum interest coverage ratio to be maintained under the debt instruments. + References No definition available. + Details
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- Definition Represents the minimum leverage ratio to be maintained under the debt instruments. + References No definition available. + Details
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- Definition Represents the minimum leverage ratio after electing to issue notes to be maintained under the debt instruments. + References No definition available. + Details
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- Definition Represents the minimum leverage ratio after the material acquisition to be maintained under the debt instruments. + References No definition available. + Details
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- Definition Represents the period of quarter after the material acquisition considered in leverage ratio under the debt instruments. + References No definition available. + Details
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- Definition Represents the minimum senior secured leverage ratio to be maintained under the debt instruments. + References No definition available. + Details
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- Definition Percentage points added to the reference rate to compute the variable rate on the debt instrument. + References No definition available. + Details
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- Definition The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR. + References No definition available. + Details
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- Details
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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 20, 22 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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Balance Type: | credit
Period Type: | instant

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- Definition Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility. + 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 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 + Details
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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + 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 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 + Details
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Balance Type: | credit
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- Definition The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility. + References No definition available. + Details
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- Details
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