Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Sep. 30, 2011
Current Assets:
Cash and cash equivalents	$ 128,065	$ 123,466
Cash held in escrow	75	1,000
Accounts receivable, less allowance for doubtful accounts of $1,043 and $391, respectively	97,694	109,317
Costs and estimated earnings in excess of billings on uncompleted contracts	77,768	51,568
Inventories, net	42,760	36,640
Income taxes receivable	553	4,071
Deferred income taxes	4,011	3,580
Prepaid expenses and other current assets	4,208	7,040
Total Current Assets	355,134	336,682
Property, plant and equipment, net	73,774	59,637
Goodwill	1,003	1,003
Intangible assets, net	14,494	15,847
Other assets	7,511	8,507
Total Assets	451,916	421,676
Current Liabilities:
Current maturities of long-term debt and capital lease obligations	916	1,140
Income taxes payable	2,360	881
Accounts payable	60,234	56,893
Accrued salaries, bonuses and commissions	19,176	22,314
Billings in excess of costs and estimated earnings on uncompleted contracts	68,617	44,523
Accrued product warranty	4,783	4,603
Other accrued expenses	5,607	7,370
Total Current Liabilities	161,693	137,724
Long-term debt and capital lease obligations, net of current maturities	3,712	4,301
Deferred compensation	2,955	3,242
Other liabilities	1,082	1,066
Total Liabilities	169,442	146,333
Commitments and Contingencies (Note I)
Stockholders' Equity:
Preferred stock, par value $.01; 5,000,000 shares authorized; none issued
Common stock, par value $.01; 30,000,000 shares authorized; 11,772,320 and 11,752,393 shares issued and outstanding, respectively	118	117
Additional paid-in capital	35,187	34,343
Retained earnings	247,921	242,254
Accumulated other comprehensive income (loss)	(752)	(1,371)
Total Stockholders' Equity	282,474	275,343
Total Liabilities and Equity	$ 451,916	$ 421,676