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v3.20.1

Equity Based Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands |  | 1 Months Ended | 3 Months Ended
--- | --- | --- | ---
Mar. 12, 2019 | Jan. 31, 2020 | Mar. 31, 2019 | Mar. 31, 2020 | Mar. 31, 2019
Additional disclosures |  |  |  |  |
Expense recognized |  |  |  | $ 3,338 | $ 11,423
Antero Midstream Partners |  |  |  |  |
Additional disclosures |  |  |  |  |
Expense recognized |  |  | $ 500 | 1,500 |
Antero Resources |  |  |  |  |
Additional disclosures |  |  |  |  |
Unamortized expense |  |  |  | 19,000 |
Midstream LTIP |  |  |  |  |
Additional disclosures |  |  |  |  |
Unamortized expense |  |  |  | $ 18,000 |
Weighted average period for recognizing unrecognized stock-based compensation expense |  |  |  | 2 years 3 months 18 days |
Restricted unit and phantom unit awards |  |  |  |  |
Number of units |  |  |  |  |
Total awarded and unvested at the beginning of the period (in shares) |  | 1,275,990 |  | 1,275,990 |
Granted (in shares) |  |  |  | 985,269 |
Vested (in shares) |  |  |  | (10,120) |
Forfeited (in shares) |  |  |  | (21,891) |
Total awarded and unvested at the end of the period (in shares) |  |  |  | 2,229,248 |
Weighted average grant date fair value |  |  |  |  |
Total awarded and unvested at the beginning of the period (in dollars per unit) |  | $ 14.38 |  | $ 14.38 |
AMP LTIP Awards converted into AMC LTIP Awards (in dollars per unit) |  |  |  | 7.23 |
Granted (in dollars per unit) |  |  |  | 8.98 |
Vested (in dollars per unit) |  |  |  | 14.51 |
Forfeited (in dollars per unit) |  |  |  | $ 11.22 |
Aggregate intrinsic value |  |  |  |  |
Total awarded and unvested at the beginning of the period |  | $ 9,685 |  | $ 9,685 |
Total awarded and unvested at the end of the period |  |  |  | 4,681 |
2017 AMGP LTIP |  |  |  |  |
Additional disclosures |  |  |  |  |
Expense recognized |  |  |  |  | 200
AM LTIP |  |  |  |  |
Additional disclosures |  |  |  |  |
Expense recognized |  |  |  | $ 1,400 |
Number of stock-based compensation awards authorized | 15,398,901 |  |  |  |
Number of shares available for future grant under the Plan |  |  |  | 12,681,835 |
Cash awards granted |  | $ 2,200 |  |  |
Vesting period for cash awards |  | 3 years |  |  |
Cash awards accrued in other liabilities |  | $ 400 |  |  |
Series B Unit, Vested and Unvested |  |  |  |  |
Additional disclosures |  |  |  |  |
Shares exchange ratio | 176.0041 |  |  |  |
Exchanged B Units |  |  |  |  |
Additional disclosures |  |  |  |  |
Expense recognized |  |  |  |  | 11,000
Shares exchanged | 17,353,999 |  |  |  |
Common stock issued in exchange | 98,600 |  |  |  |
ROIC PSUs |  |  |  |  |
Additional disclosures |  |  |  |  |
Expense recognized |  |  |  | $ 78 | $ 0
Unamortized expense |  |  |  | $ 600 |
Weighted average period for recognizing unrecognized stock-based compensation expense |  |  |  | 2 years |

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