Earnings Per Share - Schedule of Basic and Diluted Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended										6 Months Ended			9 Months Ended		12 Months Ended
	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Numerator:
Net income (loss)	$ (2,324)	$ (2,693)	$ (40,929)	$ 3,936	$ 3,655	$ 275	$ 36,655	$ 4,227	$ 3,071	$ (216)	$ (5,017)	$ 3,930	$ 2,856	$ 7,868	$ 7,081	$ (33,063)	$ 43,736	$ (8,760)
Denominator:
Weighted-average shares outstanding – basic	53,410,958				52,588,482						53,278,000	52,651,310
Effect of dilutive securities:
Employee and director stock options and restricted common shares	0				632,129						0	768,091
Contingently issuable shares	0				992,000						0	496,000
Weighted-average shares outstanding – diluted	53,411,000				54,212,097						53,278,000	53,915,144
Basic earnings per share (in dollars per share)	$ (0.04)	$ (0.05)	$ (0.77)	$ 0.07	$ 0.07	$ 0.01	$ 0.69	$ 0.08	$ 0.06	$ 0	$ (0.09)	$ 0.07	$ 0.06	$ 0.15	$ 0.14	$ (0.63)	$ 0.84	$ (0.17)
Diluted earnings per share (in dollars per share)	$ (0.04)	$ (0.05)	$ (0.77)	$ 0.07	$ 0.07	$ 0.01	$ 0.68	$ 0.08	$ 0.06	$ 0	$ (0.09)	$ 0.07	$ 0.05	$ 0.15	$ 0.13	$ (0.63)	$ 0.82	$ (0.17)