Earnings (Loss) Per Share - Narrative (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of common stock warrant and common stock options exercised (in shares)	539,500	439,238	1,646,372	2,238,537
Number of common stock issued for stock warrant and stock options exercised (in shares)	351,625	318,082	1,373,515	2,113,157
Shares surrendered in lieu of cash payment (in shares)	187,875	121,156	272,857	125,380
Common Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares excluded from calculation (in shares)	1,271,026		1,947,013