Business Combination - Estimated Fair Value of Assets Acquired and Liabilities Assumed (Details) $ in Thousands		9 Months Ended
Mar. 12, 2019 USD ($)	Sep. 30, 2019 USD ($) item
Estimated fair value of assets acquired and liabilities assumed
Goodwill		$ 902,777
Antero Midstream Partners
Estimated fair value of assets acquired and liabilities assumed
Cash and cash equivalents	$ 619,532	619,532
Other current assets	1,150	1,150
Property and equipment, net	3,639,148	3,371,427
Investments in unconsolidated affiliates	1,090,109	562,560
Customer relationships	558,000	1,542,000
Other assets, net	42,887	42,887
Total assets acquired	6,093,255	6,281,985
Accrued liabilities	87,021	87,021
Other current liabilities	537	537
Long-term debt	2,364,935	2,364,935
Contingent acquisition consideration	116,924	116,924
Asset retirement obligations	5,715	5,715
Other liabilities	2,809	2,809
Total liabilities assumed	2,611,931	2,611,931
Net assets acquired, excluding goodwill	3,481,324	3,670,054
Goodwill	1,135,266	946,536
Net assets acquired	4,616,590	$ 4,616,590
Acquisition-related costs	6,000
Property and equipment, net	(267,721)
Investments in unconsolidated affiliates	(527,549)
Customer relationships	984,000
Total assets acquired	188,730
Net assets acquired, excluding goodwill	188,730
Goodwill	(188,730)
Weighted average		22 years
Decrease in fair value		$ 10,000
Increase in Amortization		21,000
Antero Midstream Partners \| Antero Resources
Estimated fair value of assets acquired and liabilities assumed
Accounts receivable	142,312	142,312
Accounts payable	3,316	3,316
Antero Midstream Partners \| Third Party
Estimated fair value of assets acquired and liabilities assumed
Accounts receivable	117	117
Accounts payable	$ 30,674	30,674
Gathering And Processing \| Antero Midstream Partners
Estimated fair value of assets acquired and liabilities assumed
Goodwill		$ 588,000
Number of Reporting Units \| item		3
Water Handling and Treatment \| Antero Midstream Partners
Estimated fair value of assets acquired and liabilities assumed
Goodwill		$ 359,000
Number of Reporting Units \| item		2

The amount of change in acquired intangibles due to increase in amortization.

No definition available.

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- Definition

The amount of change in acquired property plant and equipment due to reversal of depreciation.

+ References

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- Definition

This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to investment in unconsolidated affiliates acquired in connection with a business combination for which the initial accounting was incomplete.

+ References

No definition available.

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This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to net assets acquired in connection with a business combination for which the initial accounting was incomplete.

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This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to total assets acquired in connection with a business combination for which the initial accounting was incomplete.

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- Definition

Amount of asset retirement obligations after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of accrued liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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- Definition

The amount of investments in unconsolidated affiliates recognized as of the acquisition date.

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- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- 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.

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to intangibles acquired in connection with a business combination for which the initial accounting was incomplete.

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- Definition

This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to property, plant, and equipment acquired in connection with a business combination for which the initial accounting was incomplete.

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- Definition

Amount of assets acquired at the acquisition date.

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- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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- Definition

The amount of liability arising from an inherited contingency (as defined) which has been recognized as of the acquisition date.

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Amount of other assets expected to be realized or consumed before one year or the normal operating cycle, if longer, acquired at the acquisition date.

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- Definition

Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables, assumed at the acquisition date.

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Amount of other liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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- Definition

The amount of identifiable intangible assets recognized as of the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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Amount of long-term debt due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of other liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

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