10. COMPENSATION

Our stock-based compensation has been granted under several stock incentive and long-term incentive plans. The plans authorize the Compensation Committee of our Board of Directors to various types of incentive compensation. Currently, we issue either stock options or restricted shares only from the 2014 Long-Term Incentive Plan (“2014 Plan”). At December 31, 2015, 4,557,185 shares were authorized for future grants under this plan.

For each stock option granted, the number of authorized shares under the 2014 Plan will be reduced on a one-for-one basis. For each restricted share granted, the number of shares authorized under the 2014 Plan will be reduced by twice the number of restricted shares. We have no set policy for sourcing shares for option grants. Historically the shares issued under options grants have been new shares.

We record non-cash compensation expense related to stock-based compensation as general and administrative expense. For the years ended December 31, 2015, 2014 and 2013, non-cash compensation expense was $3.8 million, $3.3 million and $3.0 million, related to the issuance of stock options and restricted stock. Because we do not pay significant United States federal income taxes, no amounts were recorded for tax benefits.

Stock options - Stock options have an exercise price that may not be less than the fair market value of the underlying shares on the date of grant. In general, stock options granted to participants will become exercisable over a period determined by the Compensation Committee of our Board of Directors, which in the past has been a five year life, with the options vesting over a service period of up to five years. In addition, stock options will become exercisable upon a change in control, unless provided otherwise by the Compensation Committee. Cash proceeds from the exercise of stock options were $5.7 million and $3.7 million in 2014 and 2013. There were no cash exercises of stock option in 2015.

We use the Black-Scholes model to calculate the grant date fair value of stock option awards. This fair value is then amortized to expense over the vesting period of the option. During 2015, 2014 and 2013, the weighted average assumptions shown below were used to calculate the weighted average grant date fair value of option grants. Because we have not paid cash dividends and do not anticipate paying cash dividends on the common stock in the foreseeable future, no expected dividend yield was input to the Black-Scholes model.

 

Stock option activity for the year ended December 31, 2015 is provided below:

 

The intrinsic value of a stock option is the amount by which the current market value of the underlying stock exceeds the exercise price of the option. The intrinsic value of stock options exercised in 2015, 2014 and 2013 was $0.3 million, $4.1 million and $1.2 million.

As of December 31, 2015, unrecognized compensation cost related to stock options was $1.6 million which is expected to be recognized over a weighted average period of 0.89 years.

Restricted stock - Shares of restricted stock granted under our long-term incentive plans are recorded using the fair market value of the underlying shares on the date of grant. In general, restricted stock granted to employees will vest over a period determined by the Compensation Committee which is generally a three year period, vesting in three equal parts on the first three anniversaries of the date of the grant. The following is a summary of activity in unvested restricted stock in 2015.

 

The total vest-date fair value of restricted stock awards which vested during 2015 and 2014 was $0.7 million and $0.4 million. There were no vestings of restricted stock awards in 2013. The weighted average grant-date fair value per share of unvested restricted stock awards was $3.34,  $6.98 and $5.89 at December 31, 2015, 2014 and 2013.

As of December 31, 2015, unrecognized compensation cost related to restricted stock totaled $1.2 million and is expected to be recognized over a weighted average period of 2.45 years.

Other benefit plans - We sponsor a 401(k) plan, with a company match feature, for our employees. Costs incurred in 2015, 2014 and 2013 for administering the plan, including the company match feature, were approximately $444,000 $464,000 and $182,500.