CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2021	Sep. 30, 2020
CONSOLIDATED BALANCE SHEETS
Allowance for Doubtful Accounts Receivable, Current	$ 1,949	$ 1,995
Less accumulated depreciation and amortization	$ 147,551	$ 130,534
Preferred Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Preferred Stock, Shares Authorized	10,000,000	10,000,000
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Common Stock, Shares Authorized	50,000,000	50,000,000
Common stock, shares issued	30,666,173	30,645,625
Treasury stock, shares	4,604,741	4,607,911