Compensation Plans (Tables)

12 Months Ended

Dec. 31, 2017

Schedule of performance share awards under equity incentive compensation plan

A summary of the status and activity of non-vested PSUs is presented in the following table:



	For the Years Ended December 31,
	2017				2016				2015
	PSUs		Weighted-Average Grant-Date Fair Value		PSUs		Weighted-Average Grant-Date Fair Value		PSUs		Weighted-Average Grant-Date Fair Value
Non-vested at beginning of year ⁽¹⁾	828,923		$	43.25	626,328		$	61.81	433,660		$	73.63
Granted ⁽¹⁾	977,731		$	15.86	447,971		$	26.56	320,753		$	45.34
Vested ⁽¹⁾	(94,338	)	$	85.85	(130,353	)	$	64.17	(76,438	)	$	51.76
Forfeited ⁽¹⁾	(178,825	)	$	44.99	(115,023	)	$	55.59	(51,647	)	$	73.62
Non-vested at end of year⁽¹⁾	1,533,491		$	22.97	828,923		$	43.25	626,328		$	61.81

____________________________________________


⁽¹⁾	The number of awards assumes a multiplier of one. The final number of shares of common stock issued may vary depending on the three-year performance multiplier, which ranges from zero to two.

^[1]

Schedule of Shares Settled, Performance Share Units [Table Text Block]

A summary of the shares of common stock issued to settle PSUs for the years ended December 31, 2016, and 2015, is presented in the table below:



	For the Years Ended December 31,
	2016		2015
Shares of common stock issued to settle PSUs ⁽¹⁾	44,870		288,962
Less: shares of common stock withheld for income and payroll taxes	(14,809	)	(100,683	)
Net shares of common stock issued	30,061		188,279

Multiplier earned	0.2		1.0

____________________________________________


⁽¹⁾	During the years ended December 31, 2016, and 2015, the Company issued shares of common stock for PSUs granted in 2013, and 2012. The Company and a majority of grant recipients mutually agreed to net share settle a portion of the awards to cover income and payroll tax withholdings in accordance with the Company’s Equity Plan and individual award agreements.

Schedule of Share-based Compensation, Restricted Stock Units Award Activity [Table Text Block]

A summary of the status and activity of non-vested RSUs for eligible employees is presented in the following table:



	For the Years Ended December 31,
	2017				2016				2015
	RSUs		Weighted- Average Grant-Date Fair Value		RSUs		Weighted- Average Grant-Date Fair Value		RSUs		Weighted- Average Grant-Date Fair Value
Non-vested at beginning of year	604,116		$	37.39	543,737		$	55.01	515,724		$	68.29
Granted	1,020,780		$	16.64	417,065		$	28.08	356,246		$	43.72
Vested	(246,025	)	$	43.99	(241,363	)	$	58.06	(278,289	)	$	63.12
Forfeited	(134,609	)	$	26.38	(115,323	)	$	43.52	(49,944	)	$	66.53
Non-vested at end of year	1,244,262		$	20.25	604,116		$	37.39	543,737		$	55.01

Schedule of Shares Settled, Restricted Stock Units [Table Text Block]

A summary of the shares of common stock issued to settle employee RSUs is presented in the table below:



	For the Years Ended December 31,
	2017		2016		2015
Shares of common stock issued to settle RSUs ⁽¹⁾	246,025		241,363		278,289
Less: shares of common stock withheld for income and payroll taxes	(74,747	)	(72,181	)	(91,045	)
Net shares of common stock issued	171,278		169,182		187,244

____________________________________________


⁽¹⁾	During the years ended December 31, 2017, 2016, and 2015, the Company issued shares of common stock for RSUs granted in previous years. The Company and a majority of grant recipients mutually agreed to net share settle a portion of the awards to cover income and payroll tax withholdings in accordance with the Company’s Equity Plan and individual award agreements.

Schedule of employee stock purchase plan

The fair value of ESPP shares issued during the periods reported were estimated using the following weighted-average assumptions:



	For the Years Ended December 31,
	2017		2016		2015
Risk free interest rate	0.9	%	0.4	%	0.1	%
Dividend yield	0.5	%	0.4	%	0.2	%
Volatility factor of the expected market price of the Company’s common stock	62.5	%	95.0	%	61.2	%
Expected life (in years)	0.5		0.5		0.5

Schedule of net profits plan cash payment allocation

The following table presents cash payments made or accrued under the Net Profits Plan related to periodic operations, of which the majority is recorded as general and administrative expense, and cash payments made or accrued as a result of divestitures of properties subject to the Net Profits Plan, which are recorded as a reduction to the net gain on divestiture activity line item in the accompanying statements of operations.



	For the Years Ended December 31,
	2017			2016		2015
	(in thousands)
Cash payments made or accrued related to operations	$	(54	)	$	6,608	$	3,498
Cash payments made or accrued related to divestitures	2,753			24,349		3,789
Total net settlements	$	2,699		$	30,957	$	7,287

[1]	The number of awards assumes a multiplier of one. The final number of shares of common stock issued may vary depending on the three-year performance multiplier, which ranges from zero to two.