CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2018	Sep. 30, 2017
Allowance for Doubtful Accounts Receivable, Current	$ 1,683	$ 2,030
Costs and estimated earnings on long-term contracts, progress billings	27,636	64,099
Advance payments on long-term contracts, costs incurred	$ 26,693	$ 59,772
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	30,534,786	30,468,824
Treasury stock, shares	4,623,958	4,635,622