Share-Based Payments and Other Compensation - Restricted Stock and Stock Units Activity (Details) - $ / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Restricted Stock and Stock Units
Outstanding at beginning of year, in shares	100,000	300,000
Outstanding at end of year, in shares	0	100,000
Performance-based restricted shares
Restricted Stock and Stock Units
Outstanding at beginning of year, in shares	305,543	235,746
Restricted stock granted, in shares	82,349	198,174
Vested, in shares	(6,536)	(10,821)
Expired/forfeited/cancelled, in shares	(153,801)	(117,556)
Outstanding at end of year, in shares	227,555	305,543
Weighted Average Grant Date Fair Value
Outstanding at the beginning of year (in dollars per share)	$ 4.78	$ 8.55
Granted (in dollars per share)	18.32	3.37
Vested (in dollars per share)	15.80	15.80
Expired/Forfeited/Cancelled (in dollars per share)	5.64	7.38
Outstanding at the end of year (in dollars per share)	$ 11.16	$ 4.78
Restricted Stock and RSUs
Restricted Stock and Stock Units
Outstanding at beginning of year, in shares	157,264	116,592
Restricted stock granted, in shares	101,644	154,176
Vested, in shares	(88,412)	(74,571)
Expired/forfeited/cancelled, in shares	(25,869)	(38,933)
Outstanding at end of year, in shares	144,627	157,264
Weighted Average Grant Date Fair Value
Outstanding at the beginning of year (in dollars per share)	$ 11.75	$ 15.57
Granted (in dollars per share)	17.31	10.43
Vested (in dollars per share)	13.56	13.26
Expired/Forfeited/Cancelled (in dollars per share)	12.45	11.95
Outstanding at the end of year (in dollars per share)	$ 20.72	$ 11.75