Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Cash flows from operating activities:
Net income	$ 30,851	$ 26,122
Adjustments to reconcile net income to net cash provided by operating activities:
Deferred income tax expense (benefit)	69	(1,720)
Depreciation	7,172	5,130
Amortization	179	218
Accretion of discounts on securities available-for-sale	119
Stock-based compensation expense	555	551
Bad debt expense	325	145
Inventory obsolescence reserve	1,395	3,760
Gross profit from the sale of used rental equipment	(8,174)	(9,265)
Gain on disposal of property, plant and equipment	3	(17)
Realized loss on short-term investments	1	1
Effects of changes in operating assets and liabilities:
Trade accounts and notes receivable	(2,873)	1,296
Inventories	(1,261)	(29,085)
Other current assets	3,540	1,397
Accounts payable	567	7,172
Accrued expenses and other	2,572	4,979
Deferred revenue	4,683	(827)
Income taxes payable	2,461	2,938
Prepaid income taxes	(2,165)	(980)
Net cash provided by operating activities	40,019	11,815
Cash flows from investing activities:
Purchase of property, plant and equipment	(3,049)	(3,525)
Proceeds from sale of property, plant and equipment	14	1
Investment in rental equipment	(24,593)	(13,264)
Proceeds from sale of used rental equipment	17,560	16,691
Purchase of short-term investments	(15,336)	(1,940)
Proceeds from sale of short-term investments	1,580
Net cash used in investing activities	(23,824)	(2,037)
Cash flows from financing activities:
Principal payments on mortgage loans		(7,700)
Excess tax benefit from share-based compensation	493	2,034
Proceeds from exercise of stock options and other	636	1,687
Net cash provided by (used in) financing activities	1,129	(3,979)
Effect of exchange rate changes on cash	(6)	(9)
Increase in cash and cash equivalents	17,318	5,790
Cash and cash equivalents, beginning of period	31,388	33,453
Cash and cash equivalents, end of period	$ 48,706	$ 39,243