Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Operating Activities:
Net income (loss)	$ (2,715)	$ 25,167	$ 39,925
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation	10,598	9,154	7,493
Amortization	4,848	4,549	3,469
Impairments	7,158	7,452
Stock-based compensation	99	1,929	2,256
Bad debt expense	(114)	410	959
Deferred income taxes	(425)	(348)	(1,447)
Gain on sale of investment	(1,229)
Changes in operating assets and liabilities:
Accounts receivable, net	(17,616)	39,687	15,392
Costs and estimated earnings in excess of billings on uncompleted contracts	(13,519)	8,243	35,701
Inventories	1,542	12,320	25,884
Prepaid expenses and other current assets	4,514	(5,813)	(3,432)
Other assets	(2,627)	440	(194)
Accounts payable and income taxes payable	14,487	(20,281)	(4,891)
Accrued liabilities	(4,255)	(5,392)	(40)
Billings in excess of costs and estimated earnings on uncompleted contracts	13,553	(13,762)	5,789
Other	1,188	378	120
Net cash provided by operating activities	15,487	64,133	126,984
Investing Activities:
Proceeds from sale of fixed assets	354	14	30
Purchases of property, plant and equipment	(7,347)	(4,420)	(8,081)
Proceeds from sale of investment	1,229
Increase in cash held in escrow	(1,000)
Purchase of noncontrolling interest - Powell Asia		(659)
Acquisition of Powell Canada		(23,394)
Net cash used in investing activities	(6,764)	(28,459)	(8,051)
Financing Activities:
Borrowings on US revolving line of credit			50,953
Payments on US revolving line of credit			(69,953)
Payments on UK revolving line of credit			(2,388)
Payments on UK term loan			(4,223)
Borrowings on Canadian revolving line of credit	7,810	891
Payments on Canadian revolving line of credit	(7,818)	(13,984)
Payments on Canadian term loan		(2,429)
Payments on industrial development revenue bonds	(400)	(400)	(400)
Payments on deferred acquisition payable		(4,292)	(5,220)
Payments on short-term and other financing	(1,068)	(1,087)	(13)
Proceeds from exercise of stock options	495	1,700	515
Tax benefit from exercise of stock options	180	209	291
Net cash used in financing activities	(801)	(19,392)	(30,438)
Net increase in cash and cash equivalents	7,922	16,282	88,495
Effect of exchange rate changes on cash and cash equivalents	191	1,668	(1,226)
Cash and cash equivalents at beginning of year	115,353	97,403	10,134
Cash and cash equivalents at end of year	$ 123,466	$ 115,353	$ 97,403