|12 Months Ended|
Dec. 31, 2015
(5) Equity-Based Compensation
Our general and administrative expenses include equity-based compensation costs allocated to us by Antero for grants made pursuant to: (i) the Antero Resources Corporation Long‑Term Incentive Plan (the “Antero LTIP”); (ii) profits interests awards valued in connection with the Antero reorganization pursuant to its initial public offering of common stock; and (iii) the Midstream LTIP. Equity‑based compensation expense allocated to us was $24.3 million, $11.6 million and $22.5 million for the year ended December 31, 2013, 2014 and 2015, respectively. These expenses were allocated to us based on our proportionate share of Antero’s labor costs. Antero has unamortized expense totaling approximately $232.0 million as of December 31, 2015 related to its various equity-based compensation plans, which includes the Midstream LTIP. A portion of this will be allocated to us as it is amortized over the remaining service period of the related awards.
Our general partner manages our operations and activities and Antero employs the personnel who provide support to our operations. In connection with the IPO, our general partner adopted the Midstream LTIP, pursuant to which non‑employee directors of our general partner and certain officers, employees and consultants of our general partner and its affiliates are eligible to receive awards representing ownership interests in the Partnership. An aggregate of 10,000,000 common units may be delivered pursuant to awards under the Midstream LTIP, subject to customary adjustments. A total of 7,947,771 common units are available for future grant under the Midstream LTIP as of December 31, 2015. Restricted units and phantom units granted under the Midstream LTIP vest subject to the satisfaction of service requirements, upon the completion of which common units in the Partnership are delivered to the holder of the restricted units or phantom units. Compensation related to each restricted unit and phantom unit award is recognized on a straight-line basis over the requisite service period of the entire award. The grant date fair values of these awards are determined based on the closing price of the Partnership’s common units on the date of grant. These units are accounted for as if they are distributed by the Partnership to Antero. Antero recognizes compensation expense for the units awarded and a portion of that expense is allocated to the Partnership. Antero allocates equity-based compensation expense to the Partnership based on our proportionate share of Antero’s labor costs. The Partnership’s portion of the equity-based compensation expense is included in general and administrative expenses, and recorded as a credit to the applicable classes of partners’ capital.
A summary of restricted unit and phantom unit awards activity during the year ended December 31, 2015 is as follows:
Intrinsic values are based on the closing price of the Partnership’s common units on the referenced dates. Midstream LTIP unamortized expense of $46.1 million at December 31, 2015 is expected to be recognized over a weighted average period of approximately 2.9 years and our proportionate share will be allocated to us as it is recognized. We paid $4.8 million in minimum statutory tax withholdings for restricted and phantom units that vested during 2015, which is included in the “Issuance of common units in Antero Midstream Partners LP upon vesting of equity-based compensation awards” line item in the Combined Consolidated Statements of Partners’ Capital.
The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details.
Reference 1: http://www.xbrl.org/2003/role/presentationRef