v3.6.0.2

Quarterly Financial Information (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2015 | Sep. 30, 2015 | Jun. 30, 2015 | Mar. 31, 2015 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Quarterly Financial Information |  |  |  |  |  |  |  |  |  |  |
Total operating revenues | $ 166,854 | $ 150,475 | $ 136,810 | $ 136,072 | $ 131,693 | $ 81,704 | $ 88,093 | $ 85,834 | $ 590,211 | $ 387,324 | $ 266,274
Total operating expenses | 82,953 | 76,192 | 83,503 | 89,452 | 79,793 | 37,012 | 51,333 | 51,923 | 332,100 | 220,061 | 132,216
Operating income | 83,901 | 74,283 | 53,307 | 46,620 | 51,900 | 44,692 | 36,760 | 33,911 | 258,111 | 167,263 | 134,058
Net income (loss) | 73,351 | 70,524 | 49,912 | 42,916 | 49,008 | 42,648 | 35,124 | 32,325 |  |  |
Pre-Water Acquisition net income attributed to parent |  |  |  |  |  | (7,841) | (15,674) | (16,678) |  | (40,193) | (22,234)
General partner's interest in net income attributable to incentive distribution rights | (7,557) | (4,806) | (2,731) | (1,850) | (969) | (295) |  |  | (16,944) | (1,264) |
Limited partners' interest in net income | $ 65,794 | $ 65,718 | $ 47,181 | $ 41,066 | $ 48,039 | $ 34,512 | $ 19,450 | $ 15,647 | $ 219,759 | $ 117,648 | $ 7,422
Basic and Diluted: |  |  |  |  |  |  |  |  |  |  |
Common units (in dollars per share) | $ 0.37 | $ 0.37 | $ 0.27 | $ 0.23 | $ 0.27 | $ 0.23 | $ 0.13 | $ 0.10 | $ 1.24 | $ 0.76 | $ 0.05
Subordinated units (in dollars per share) | $ 0.37 | $ 0.37 | $ 0.27 | $ 0.23 | $ 0.27 | $ 0.22 | $ 0.13 | $ 0.10 | $ 1.24 | $ 0.73 | $ 0.05

X
- Definition Aggregate amount of net income allocated to general partners subsequent to IPO. + References No definition available. + Details
Name: | am_NetIncomeLossAllocatedToGeneralPartnersPostIpo
Namespace Prefix: | am_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Aggregate amount of net income allocated to limited partners subsequent to IPO. + References No definition available. + Details
Name: | am_NetIncomeLossAllocatedToLimitedPartnersPostIpo
Namespace Prefix: | am_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Per unit of ownership amount after tax of income (loss) available to outstanding limited partnership (LP) common unit-holder. + References No definition available. + Details
Name: | am_NetIncomeLossPerOutstandingLimitedPartnershipCommonUnitBasicAndDilutedNetOfTax
Namespace Prefix: | am_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition Per unit of ownership amount after tax of income (loss) available to Subordinated unit holder in limited partnership. + References No definition available. + Details
Name: | am_NetIncomeLossPerOutstandingLimitedPartnershipSubordinatedUnitBasicAndDilutedNetOfTax
Namespace Prefix: | am_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition This concept does not have a custom type definition. + References No definition available. + Details
Name: | am_NetIncomeLossPerOutstandingLimitedPartnershipUnitBasicAndDilutedNetOfTaxAbstract
Namespace Prefix: | am_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Aggregate amount of pre-acquisition net income allocated to parent. + References No definition available. + Details
Name: | am_NetIncomeLossPreAcquisitionNetIncomeAllocatedToParent
Namespace Prefix: | am_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Aggregate amount of net income allocated to limited partners. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770 + Details
Name: | us-gaap_NetIncomeLossAllocatedToLimitedPartners
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense. + References No definition available. + Details
Name: | us-gaap_OperatingExpenses
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The net result for the period of deducting operating expenses from operating revenues. + References No definition available. + Details
Name: | us-gaap_OperatingIncomeLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
Name: | us-gaap_Revenues
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_SelectedQuarterlyFinancialInformationAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration