Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Cash flows from operating activities:
Net income (loss)	$ (45,970,000)	$ (32,641,000)	$ 36,911,000
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Deferred income tax expense (benefit)	4,209,000	(943,000)	818,000
Rental equipment depreciation	14,523,000	13,948,000	12,182,000
Property, plant and equipment depreciation	5,391,000	5,599,000	5,592,000
Impairment of rental assets	1,814,000
Goodwill impairment		1,843,000
Accretion of discounts on short-term investments	110,000	225,000	49,000
Stock-based compensation expense	5,220,000	4,539,000	4,119,000
Bad debt expense	763,000	2,147,000	833,000
Inventory obsolescence expense	10,590,000	3,887,000	2,617,000
Write-down of inventories	622,000
Gross profit from sale of used rental equipment	(404,000)	(3,208,000)	(9,031,000)
Loss (gain) on disposal of property, plant and equipment	8,000	26,000	(64,000)
Realized loss on short-term investments	5,000	7,000	0
Excess tax expense from stock-based compensation	(1,411,000)	(1,083,000)
Effects of changes in operating assets and liabilities:
Trade accounts and notes receivable	(3,428,000)	7,088,000	25,605,000
Income tax receivable	4,078,000	(14,799,000)	(2,639,000)
Inventories	5,193,000	9,661,000	(10,452,000)
Costs and estimated earnings in excess of billings			12,400,000
Prepaid expenses and other current assets	(523,000)	997,000	998,000
Prepaid income taxes	1,475,000	1,753,000	353,000
Accounts payable trade	(1,942,000)	(834,000)	(11,756,000)
Accrued expenses and other	(2,149,000)	(6,004,000)	(3,435,000)
Deferred revenue	11,000	(3,567,000)	2,685,000
Income taxes payable	120,000	(10,000)	(135,000)
Net cash provided by (used in) operating activities	(1,695,000)	(11,369,000)	67,650,000
Cash flows from investing activities:
Purchase of property, plant and equipment	(1,867,000)	(2,189,000)	(6,792,000)
Proceeds from the sale of property, plant and equipment			27,000
Investment in rental equipment	(502,000)	(3,973,000)	(26,719,000)
Proceeds from the sale of used rental equipment	1,584,000	4,278,000	16,390,000
Purchases of short-term investments	(25,791,000)	(6,306,000)	(21,610,000)
Proceeds from the sale of short-term investments	16,368,000	7,902,000	2,000,000
Net cash used in investing activities	(10,208,000)	(288,000)	(36,704,000)
Cash flows from financing activities:
Net payments under line of credit			(931,000)
Excess tax benefits from stock-based compensation			178,000
Proceeds from exercise of stock options and other			424,000
Net cash used in financing activities			(329,000)
Effect of exchange rate changes on cash	(149,000)	614,000	14,000
Increase (decrease) in cash and cash equivalents	(12,052,000)	(11,043,000)	30,631,000
Cash and cash equivalents, beginning of fiscal year	22,314,000	33,357,000	2,726,000
Cash and cash equivalents, end of fiscal year	$ 10,262,000	$ 22,314,000	$ 33,357,000