Summary of Significant Accounting Policies - Stock option equivalents (Details) - shares shares in Thousands	Sep. 30, 2019	Sep. 30, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total number of common stock equivalents outstanding (in shares)	636	395
Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total number of common stock equivalents outstanding (in shares)	19	37
Warrants [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total number of common stock equivalents outstanding (in shares)	193	193
Restricted Stock Units (RSUs) [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total number of common stock equivalents outstanding (in shares)	406	154
Deferred Issuance of Vested Common Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total number of common stock equivalents outstanding (in shares)	18	0
Restricted stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total number of common stock equivalents outstanding (in shares)	0	11