Basis of Presentation and Significant Accounting Policies - Computation of Basic and Diluted Weighted Average Shares Used in Earnings per Share Calculations (Detail) - shares	3 Months Ended		6 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
Earnings Per Share, Basic and Diluted [Abstract]
Denominator for basic earnings per share - weighted average common shares (in shares)	5,278,500	4,461,310	5,232,449	4,459,675
Effect of dilutive options (treasury method) (in shares)	0	0	0	0
Denominator for diluted earnings per share - adjusted weighted average common shares (in shares)	5,278,500	4,461,310	5,232,449	4,459,675
Options and warrants outstanding during each period, but not included in the computation of diluted earnings per share because they are antidilutive (in shares)	2,076,083	2,242,269	2,076,083	2,242,269