Stock Based Compensation
3 Months Ended
Mar. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]  
Stock Based Compensation
Stock Based Compensation
During the year ended December 31, 2013, the Board of Directors approved the 2013 Omnibus Incentive Plan (the “Plan”). The Plan provides for a maximum of 15.0 million shares of the Company’s common stock to be issued for qualified and non-qualified options, stock appreciation rights, restricted stock and RSUs, OP Units, performance awards and other stock-based awards.

During the three months ended March 31, 2018 and the year ended December 31, 2017, the Company granted RSUs to certain employees. The RSUs are divided into multiple tranches, which are all subject to service-based vesting conditions. Certain tranches are also subject to performance-based or market-based vesting conditions, which contain a threshold, target, and maximum number of units which can be earned. The number of units actually earned for each tranche is determined based on performance during a specified performance period. Tranches that only have a service-based component can only earn a target number of units. The aggregate number of RSUs granted, assuming that the target level of performance is achieved, was 0.7 million and 0.6 million for the three months ended March 31, 2018 and year ended December 31, 2017, respectively, with vesting periods ranging from one to five years. For the performance-based and service-based RSUs granted under the Plan, fair value is based on the Company grant date stock price. For the market-based RSUs granted during the three months ended March 31, 2018 and year ended December 31, 2017, the Company calculated the grant date fair values per unit using a Monte Carlo simulation based on the probability of satisfying the market performance hurdles over the remainder of the performance period based on the Company’s historical common stock performance relative to the other companies within the FTSE NAREIT Equity Shopping Centers Index as well as the following significant assumptions: (i) volatility of 29.0% to 32.0% and 22.0% to 23.0%, respectively; (ii) a weighted average risk-free interest rate of 2.43% to 2.53% and 1.20% to 1.41%, respectively; and (iii) the Company’s weighted average common stock dividend yield of 5.6% and 4.0% to 4.6%, respectively.

During the three months ended March 31, 2018 and 2017, the Company recognized $2.5 million and $2.1 million of equity compensation expense. These amounts are included in General and administrative expense in the Company’s unaudited Condensed Consolidated Statements of Operations. As of March 31, 2018, the Company had $20.5 million of total unrecognized compensation expense related to unvested stock compensation expected to be recognized over a weighted average period of approximately 2.5 years.