Stock Incentive Plans

12 Months Ended

Dec. 31, 2019

Share-based Payment Arrangement [Abstract]

In May 2016, our shareholders approved the 2016 Long-Term Incentive Plan (“2016 Plan”), which authorized up to 10,000,000 shares of common stock to be issued at the discretion of the Compensation Committee of the Board of Directors. Awards granted after May 5, 2016 are issued out of the 2016 Plan. The awards granted under the Amended and Restated 2005 Long-Term Incentive Plan continue to vest and options expire ten years from the date of grant. Our non-employee directors, officers and key employees are eligible to participate in the 2016 Plan. The 2016 Plan allows for the issuance of, among other things, stock options, stock appreciation rights, restricted stock, deferred stock units and dividend equivalent rights. Vesting periods for options, deferred stock units and restricted shares generally range from three to five years.

Under our long-term incentive plan, certain restricted stock awards are market, performance and time-based. For market and performance based awards, we will grant a target number of restricted stock units, with the ultimate award determined by the total

shareholder return and operating performance metrics, measured in each case over a measurement period of two to three years. Generally awards vest over two to three years after the end of the performance period with a portion vesting immediately at the end of the performance periods. The expected term represents the period from the grant date to the end of the performance period. Compensation expense for these performance grants is measured based on the probability of achievement of certain performance goals and is recognized over both the performance period and vesting period. For the portion of the grant for which the award is determined by the operating performance metrics, the compensation cost is based on the grant date closing price and management’s estimate of corporate achievement of the financial metrics. If the estimated number of performance based restricted stock to be earned changes, an adjustment will be recorded to recognize the accumulated difference between the revised and previous estimates. For the portion of the grant determined by the total shareholder return, management used a Monte Carlo model to assess the fair value and compensation cost. Forfeitures are accounted for as they occur.

The following table summarizes compensation expense (a component of general and administrative expenses and property operating expenses) recognized for the periods presented (in thousands):



	Year Ended December 31,
	2019		2018		2017
Stock options	$	—	$	—	$	10
Restricted stock	25,047		27,646		19,092
	$	25,047	$	27,646	$	19,102

Restricted Stock

The fair value of the restricted stock is equal to the market price of the company’s common stock on the date of grant and is amortized over the vesting periods. As of December 31, 2019, there was $30,755,000 of total unrecognized compensation expense related to unvested restricted stock that is expected to be recognized over a weighted-average period of two years. The following table summarizes information about non-vested restricted stock incentive awards as of and for the year ended December 31, 2019:



	Restricted Stock
	Number of Shares (000's)		Weighted-Average Grant Date Fair Value
Non-vested at December 31, 2018	1,220		$	62.56
Vested	(364	)	52.15
Granted	367		85.80
Terminated	(117	)	66.25
Non-vested at December 31, 2019	1,106		$	70.26