Summary of Significant Accounting Policies - Basic and Diluted Common Shares (Details) - shares	12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Basic weighted-average shares (in shares)	12,435,923	12,464,496
Effect of dilutive securities:
Diluted weighted-average shares (in shares)	12,435,923	12,502,254
Options
Effect of dilutive securities:
Effect of dilutive securities (in shares)	0	15,109
Unvested restricted stock units
Effect of dilutive securities:
Effect of dilutive securities (in shares)	0	22,649