Compensation Plans

3 Months Ended

Mar. 31, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Note 7 - Compensation Plans

Performance Share Units

The Company grants performance share units (“PSUs”) to eligible employees as part of its long-term equity incentive compensation program. The number of shares of the Company’s common stock issued to settle PSUs ranges from zero to two times the number of PSUs awarded and is determined based on certain performance criteria over a three-year measurement period. The performance criteria for PSUs are based on a combination of the Company’s annualized Total Shareholder Return (“TSR”) for the performance period and the relative performance of the Company’s TSR compared with the annualized TSR of certain peer companies for the performance period. Compensation expense for PSUs is recognized within general and administrative and exploration expense over the vesting periods of the respective awards.

Total compensation expense recorded for PSUs was $2.4 million and $2.5 million for the three months ended March 31, 2018, and 2017, respectively. As of March 31, 2018, there was $15.6 million of total unrecognized compensation expense related to non-vested PSU awards, which is being amortized through 2020. There have been no material changes to the outstanding and non-vested PSUs during the three months ended March 31, 2018.

Employee Restricted Stock Units

The Company grants restricted stock units (“RSUs”) to eligible employees as part of its long-term equity incentive compensation program. Each RSU represents a right to receive one share of the Company’s common stock upon settlement of the award at the end of the specified vesting period. Compensation expense for RSUs is recognized within general and administrative expense and exploration expense over the vesting periods of the respective awards.

Total compensation expense recorded for employee RSUs was $2.7 million and $2.5 million for the three months ended March 31, 2018, and 2017, respectively. As of March 31, 2018, there was $16.2 million of total unrecognized compensation expense related to non-vested RSU awards, which is being amortized through 2020. There have been no material changes to the outstanding and non-vested RSUs during the three months ended March 31, 2018.