Summary of Significant Accounting Policies - Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015	Jun. 23, 2015	Feb. 04, 2011
Numerator:
Basic and diluted net income (loss)	$ 791	$ (5,008)
Denominator:
Basic weighted average shares outstanding	22,389,834	21,995,460
Diluted weighted average shares outstanding	22,625,896	21,995,460
Basic income (loss) per share	$ 0.04	$ (0.23)
Diluted income (loss) per share	$ 0.04	$ (0.23)
6.00% Notes
Earnings (Loss) Per Share
Stated interest rate (percent)	6.00%		6.00%	6.00%
7.50% Senior Convertible Notes (the "7.50% Notes")
Earnings (Loss) Per Share
Stated interest rate (percent)	7.50%	7.50%	7.50%		7.50%
7.50% Senior Exchange Convertible Notes due 2016 (“7.50% Exchange Notes”)
Earnings (Loss) Per Share
Stated interest rate (percent)					7.50%