Income (loss) Per Share - Antidilutive Securities (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Shares underlying convertible preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from EPS (shares)	760,000	728,000	760,000	728,000
“In the money” stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from EPS (shares)	34,534	0	0	36,000
“Out of the money” stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from EPS (shares)	285,259	289,514	285,259	253,514
“In the money” warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from EPS (shares)	0	0	0	958,152
“Out of the money” warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from EPS (shares)	7,392,966	7,497,642	7,392,966	6,539,490
Shares underlying convertible notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from EPS (shares)	1,056,068	1,056,068	1,056,068	1,056,068
Shares underlying convertible accrued interest on convertible notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from EPS (shares)	136,936	90,472	136,936	90,472