Stock Based Compensation

6 Months Ended

Jun. 30, 2015

Share-based Compensation [Abstract]

Stock Based Compensation

9. Stock Based Compensation

During the six months ended June 30, 2015, we awarded 216,975 shares of restricted stock awards to certain employees, which had a fair value of $4,708 on the date of approval by the Compensation Committee of the Board of Directors. These restricted stock awards were issued based upon the achievement of certain corporate performance goals for the calendar year 2014 and generally vest over a period of three years. Additionally, during the six months ended June 30, 2015, we awarded 17,385 shares of restricted stock to non-employee members of the Board of Directors, which had a fair value of $350 on the date of approval. These restricted stock awards vest over a one-year period.

Compensation expense is charged to earnings over the vesting periods for the shares expected to vest except if the recipient is not required to provide future service in exchange for vesting of such shares. If vesting of a recipient's restricted stock award is not contingent upon future service, the expense is recognized immediately at the date of grant. During the six months ended June 30, 2015 and 2014, we recognized $1,250 and $1,451, respectively, of compensation expense related to restricted stock awards granted to our Chief Executive Officer for which future service was not required.

Additionally, during the six months ended June 30, 2015, 264,432 Long-Term Incentive Program ("LTIP") performance units ("2015 LTIP Unit Awards") were granted to certain employees. The 2015 LTIP Unit Awards had a fair value of $2,531 on the grant date as determined by a lattice-binomial option-pricing model based on a Monte Carlo simulation. The 2015 LTIP Unit Awards vest based upon the relative total shareholder return ("TSR") of our common stock compared to the TSRs of the MSCI US REIT Index and the NAREIT Industrial Index. The TSR for the granted units is calculated based upon the performance from January 1, 2015 through December 31, 2017. Compensation expense is charged to earnings on a straight-line basis over the performance period. At the end of the performance period each participant will be issued shares of our common stock equal to the maximum shares issuable to the participant for the performance period multiplied by a percentage, ranging from 0% to 100%, based on our TSR as compared to the TSRs of the MSCI US REIT Index and the NAREIT Industrial Index. The participant is also entitled to dividend equivalents for shares issued pursuant to vested 2015 LTIP Unit Awards. The dividend equivalents represent any common dividends that would have been paid with respect to such issued shares after the grant of the 2015 LTIP Unit Awards and prior to the date of settlement.

We recognized $1,506 and $3,322 for the three months ended June 30, 2015 and 2014, and $4,067 and $4,897 for the six months ended June 30, 2015 and 2014, respectively, in amortization related to restricted stock awards and LTIP performance units. Restricted stock award and LTIP performance unit amortization capitalized in connection with development activities was not significant. At June 30, 2015, we had $8,558 in unrecognized compensation related to unvested restricted stock awards and LTIP performance units, which is expected to be recognized over a weighted average 1.01 year term.