Equity-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2017

Equity-Based Compensation

Schedule of total equity-based compensation expense recognized in entity's consolidated statements of operations

	2017		2016		2015
Total equity-based compensation expense	$	11,730	$	13,064	$	6,935

Summary of restricted stock and restricted stock unit award activity

		Weighted
		Average
		Grant-Date
	Number	Fair Value
		(per share)
Non-vested units as of January 1, 2017	2,338	$	4.02
Granted	785		4.70
Vested	(199)		10.87
Forfeited	(111)		3.56
Non-vested units as of December 31, 2017	2,813	$	3.75

Summary of performance based share unit awards activity

		Weighted
		Average
		Grant-Date
	Number	Fair Value
		(per share)
Non-vested units as of January 1, 2017	2,958	$	4.63
Granted	1,012		5.85
Forfeited	(125)		3.87
Canceled	(78)		25.63
Vested	(82)		25.63
Non-vested units as of December 31, 2017	3,685	$	4.08

Shedule of assumptions used to estimate the fair value of performance-based share units granted

	2017			2015
Risk-free interest rate		1.5	%		1.0	%
Expected volatility		76.3	%		37.7	%
Term (in years)		2.8			2.8
Fair Value (per share)	$	5.85		$	9.66

Summary of non-qualified stock option activity

		Weighted		Weighted
		Average		Average	Aggregate
		Exercise		Contractual	Intrinsic
	Number	Price		Term	Value (1)
		(per option)		(years)
Options outstanding as of January 1, 2017	1,098	$	16.73	4.3	$	—
Expired	(96)	$	16.35
Options outstanding as of December 31, 2017	1,002	$	16.77	3.4	$	—
Exercisable as of December 31, 2017	1,002	$	16.77	3.4	$	—

• The intrinsic value of a stock option is the amount by which the market value of the underlying stock exceeds the exercise price of the option at year-end.

Schedule of compensation costs related to the ESPP

	2017		2016		2015
Unrecognized compensation expense	$	—	$	—	$	233
Recognized compensation expense		—		90		248
Total ESPP compensation expense	$	—	$	90	$	481

Schedule of fair value of each purchase right granted under the Employee Stock Purchase Plan

		2015
Weighted-average fair value (per award)		$	1.54
Assumptions:
	Risk-free interest rate		0.4	%
	Expected option life		1.0
	Expected volatility		70.0	%