Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Dec. 31, 2020	Sep. 30, 2020
Current Assets:
Cash and cash equivalents	$ 134,016	$ 160,216
Short-term investments	15,694	18,705
Accounts receivable, less allowance for doubtful accounts of $493 and $510	77,294	69,957
Contract assets	47,886	50,995
Inventories	29,019	28,968
Income taxes receivable	146	467
Prepaid expenses	3,937	4,402
Other current assets	2,299	1,948
Total Current Assets	310,291	335,658
Property, plant and equipment, net	114,866	114,372
Operating lease assets, net	4,711	5,217
Goodwill and intangible assets, net	1,116	1,161
Deferred income taxes	3,726	3,644
Other assets	13,600	12,226
Total Assets	448,310	472,278
Current Liabilities:
Current maturities of long-term debt	400	400
Accounts payable	28,012	35,029
Contract liabilities	70,939	79,445
Accrued compensation and benefits	10,129	21,739
Accrued product warranty	2,675	2,771
Current operating lease liabilities	2,154	2,352
Income taxes payable	1,799	1,861
Other current liabilities	10,720	9,350
Total Current Liabilities	126,828	152,947
Long-term debt, net of current maturities	0	400
Deferred compensation	8,197	6,710
Long-term operating lease liabilities	3,075	3,434
Other long-term liabilities	2,365	2,161
Total Liabilities	140,465	165,652
Commitments and Contingencies (Note F)
Stockholders' Equity:
Preferred stock, par value $0.01; 5,000,000 shares authorized; none issued	0	0
Common stock, par value $0.01; 30,000,000 shares authorized; 12,480,891 and 12,422,411 shares issued, respectively	125	124
Additional paid-in capital	62,259	61,998
Retained earnings	290,624	294,016
Treasury stock, 806,018 shares at cost	(24,999)	(24,999)
Accumulated other comprehensive loss	(20,164)	(24,513)
Total Stockholders' Equity	307,845	306,626
Total Liabilities and Stockholders' Equity	$ 448,310	$ 472,278