Share-based compensation (Tables)

12 Months Ended

Dec. 31, 2017

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Summary of options, fully vested and exercisable

A summary of activity under our Stock Incentive Plan during the year ended December 31, 2017 is presented below:



Options	Number		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (years)	Aggregate Intrinsic Value
Outstanding at January 1, 2017	359,570		$	24.95
Exercised	(61,648	)
Forfeited/expired	(131,165	)	51.00
Outstanding, fully vested and exercisable at December 31, 2017 (1)	166,757		$	11.02	1.24	$	1,954


⁽¹⁾	As the result of actions in 2011 that were determined to be a "change of control" under the Stock Incentive Plan, all options will remain exercisable for their respective remaining term, regardless of whether the awardees remain employees of Century. Of the 166,757 outstanding options at December 31, 2017 there are 149,257 options with an exercise price of $6.55 per share that expire in May 2019.

Summary of service-based share awards activity



Service-based share awards	Number
Outstanding at January 1, 2017	741,036
Granted	337,951
Vested	(172,526	)
Forfeited	(61,053	)
Outstanding at December 31, 2017	845,408



	Year ended December 31,
Service-based share awards	2017		2016		2015
Weighted average per share fair value of service-based share grants	$	8.92	$	7.14	$	4.21
Total intrinsic value of option exercises	624		—		—

Summary of share-based compensation expense

The following table summarizes the compensation cost recognized for the years ended December 31, 2017, 2016 and 2015 for all options, service-based and performance-based share awards. The compensation cost is included as part of selling, general and administrative expenses in our Consolidated Statements of Operations.



	Year ended December 31,
	2017		2016		2015
Share-based compensation expense reported:
Performance-based share expense	$	3,968	$	2,402	$	2,645
Service-based share expense	3,433		2,105		428
Total share-based compensation expense before income tax	7,401		4,507		3,073
Income tax	—		—		—
Total share-based compensation expense, net of income tax	$	7,401	$	4,507	$	3,073