CAPITAL STOCK AND SHARE-BASED COMPENSATION (Tables)

12 Months Ended

Dec. 31, 2016

Employee Stock Purchase Plan Period	Shares Issued	Price
2014 and Prior	2,899,528	$	13.78
January 1, 2015 to March 31, 2015	24,368		22.76
April 1, 2015 to June 30, 2015	15,750		33.77
July 1, 2015 to September 30, 2015	18,984		32.27
October 1, 2015 to December 31, 2015	19,082		33.42
January 1, 2016 to March 31, 2016	13,850		41.09
April 1, 2016 to June 30, 2016	14,236		42.91
July 1, 2016 to September 30, 2016	16,520		40.32
October 1, 2016 to December 31, 2016	16,882		36.24
	3,039,200

Stock Options

We use the Black-Scholes option pricing model to estimate the fair value of our stock options. There were 268,538, 590,647 and 250,000 options granted during 2016, 2015 and 2014, respectively. Stock option compensation expense included in general and administrative expense in our accompanying consolidated statements of operations was $6.3 million, $3.8 million and $0.1 million for 2016, 2015 and 2014, respectively.

The fair value of the 2016 awards were estimated using the following assumptions:

	Risk Free Rate	1.19% - 1.58%
	Expected Volatility	53.44 % - 54.89%
	Expected Term	5.86 - 6.25 years
	Weighted Average Fair Value	$25.99

We used the simplified method to estimate the expected term for the stock options granted during 2016.

The following table presents our stock option activity for 2016:
		Number of Shares	Weighted Average Exercise Price		Weighted Average Contractual Life (Years)
Outstanding options at January 1, 2016		838,494	$	30.18	9.31
	Granted	268,538		37.21
	Exercised	0		0
	Canceled, forfeited or expired	(98,875)		35.45
Outstanding options at December 31, 2016		1,008,157	$	31.54	8.42
Exercisable options at December 31, 2016		281,458	$	28.86	8.21

The aggregate intrinsic value of our outstanding options and exercisable options at December 31, 2016 was $11.9 million and $3.9 million, respectively. There were no options exercised during 2016. Total intrinsic value of options exercised was $0.2 million and $0.1 million for 2015 and 2014, respectively.

The following table presents our non-vested stock option award activity for 2016:
		Number of Shares	Weighted Average Grant Date Fair Value
		Number of Shares	Weighted Average Grant Date Fair Value
Non-vested stock options at January 1, 2016		775,994	$	30.47
	Granted	268,538		37.21
	Vested	(219,872)		29.55
	Forfeited	(97,961)		35.38
Non-vested stock options at December 31, 2016		726,699	$	32.58

At December 31, 2016, there was $7.2 million of unrecognized compensation cost related to stock options that we expect to be recognized over a weighted-average period of 2.1 years.


Non-Vested Stock

We issue shares of non-vested stock with vesting terms ranging from one to six years. The compensation expense is determined based on the market price of our common stock at the date of grant applied to the total number of shares that are anticipated to fully vest. Non-vested stock compensation expense included in general and administrative expenses in our accompanying consolidated statements of operations was $2.3 million, $5.0 million and $4.6 million for 2016, 2015 and 2014, respectively.

The following table presents our non-vested stock award activity for 2016:
		Number of Shares	Weighted Average Grant Date Fair Value
Non-vested stock at January 1, 2016		500,888	$	18.24
	Granted	21,202		50.55
	Vested	(222,783)		18.00
	Canceled, forfeited or expired	(89,929)		17.26
Non-vested stock at December 31, 2016		209,378	$	22.20

The weighted average grant date fair value of non-vested stock granted was $50.55, $28.48 and $16.38 in 2016, 2015, and 2014, respectively.

At December 31, 2016, there was $1.4 million of unrecognized compensation cost related to non-vested stock award payments that we expect to be recognized over a weighted average period of 0.9 years.


Non-Vested Stock Units - Service-Based

Service-based non-vested stock unit compensation expense included in general and administrative expenses in our accompanying consolidated statements of operations was $3.6 million and $1.0 million for 2016 and 2015, respectively.



The following table presents our service-based non-vested stock units activity for 2016:
		Number of Shares	Weighted Average Grant Date Fair Value
Non-vested stock units at January 1, 2016		183,332	$	37.89
	Granted	147,896		45.60
	Vested	(32,607)		38.81
	Canceled, forfeited or expired	(49,192)		39.38
Non-vested stock units at December 31, 2016		249,429	$	42.05

The weighted average grant date fair value of service-based non-vested stock units granted was $45.60 and $37.98 in 2016 and 2015, respectively.

At December 31, 2016, there was $6.7 million of unrecognized compensation cost related to our service-based non-vested stock units that we expect to be recognized over a weighted average period of 2.2 years.


The following table presents our performance-based non-vested stock units activity for 2016:
		Number of Shares	Weighted Average Grant Date Fair Value
Non-vested stock units at January 1, 2016		151,063	$	39.44
	Granted	182,796		46.29
	Vested	(44,729)		34.83
	Canceled, forfeited or expired	(64,273)		42.41
Non-vested stock units at December 31, 2016		224,857	$	45.08


The following table presents our market-based non-vested stock units activity for 2016:
		Number of Shares	Weighted Average Grant Date Fair Value
Non-vested stock units at January 1, 2016		164,534	$	10.51
	Granted (1)	93,257		10.51
	Vested	(248,654)		10.51
	Canceled, forfeited or expired	(9,137)		10.51
Non-vested stock units at December 31, 2016		-	$	0


(1)	Represents shares awarded upon achievement of maximum payout.