Equity Transactions and Stock-Based Compensation Plans (Schedule of Stock Option Activity) (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($) $ / shares shares
Number of Shares [Abstract]
Options, Outstanding, Number, Beginning | shares	4,384,425
Granted | shares	268,185
Options, Forfeitures | shares	(382,700)
Options, Outstanding, Number, Ending | shares	4,269,910
Options, Exercisable, Number | shares	3,288,463
Weighted-Average Price Per Share [Abstract]
Options, Outstanding, Weighted Average Exercise Price, Beginning | $ / shares	$ 7.42
Options, Grants in Period, Weighted Average Exercise Price | $ / shares	6.40
Options, Forfeitures, Weighted Average Exercise Price | $ / shares	13.82
Options, Outstanding, Weighted Average Exercise Price, Ending | $ / shares	6.78
Options, Exercisable, Weighted Average Exercise Price | $ / shares	$ 7.90
Weighted-Average Remaining Contract Life [Abstract]
Options, Outstanding, Weighted Average Remaining Contractual Term	4 years 6 months
Options, Exercisable, Weighted Average Remaining Contractual Term	3 years 4 months 24 days
Options, Outstanding, Intrinsic Value | $	$ 1,576
Options, Exercisable, Intrinsic Value | $	$ 525