Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Statement of Financial Position [Abstract]
Doubtful accounts	$ 249	$ 592
Serial preferred shares, shares authorized (in shares)	1,000,000	1,000,000
Common shares, par value (in dollars per share)	$ 1	$ 1
Common shares, shares authorized (in shares)	10,000,000	10,000,000
Common shares, shares issued (in shares)	5,916,000	5,777,000
Common shares, shares outstanding (in shares)	5,916,000	5,777,000