Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands	3 Months Ended
	Aug. 31, 2011	Aug. 31, 2010
Cash flows from operating activities:
Net income	$ 8,505	$ 5,221
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	12,835	11,952
Put option loss		952
Realized gain on redemption of trading securities		(952)
Remeasurement loss on foreign currency	66	48
Provision for losses on accounts receivable	6	11
Gain on sale of rental and lease equipment	(2,412)	(2,420)
Gain on bargain purchase, net of deferred taxes	(3,194)	(153)
Stock compensation expense	326	195
Excess tax benefit for share based compensation	(37)	(14)
Deferred income taxes	2,384	(671)
Changes in operating assets and liabilities:
Accounts receivable	(1,434)	(878)
Other assets	2,080	(1,770)
Accounts payable	(1,883)	(70)
Accrued expenses	(1,417)	2,988
Deferred revenue	440	156
Net cash provided by operating activities	16,265	14,595
Cash flows from investing activities:
Proceeds from sale of rental and lease equipment	5,456	6,507
Cash paid for acquisition	(10,673)
Proceeds from acquisition purchase price adjustment		153
Payments for purchase of rental and lease equipment	(24,130)	(24,272)
Redemptions of investments, trading		14,275
Payments for purchase of other property	(108)	(183)
Net cash used in investing activities	(29,455)	(3,520)
Cash flows from financing activities:
Proceeds from issuance of common stock		149
Excess tax benefit for stock options exercised	37	14
Payment of dividends	(4,796)	(3,594)
Net cash used in financing activities	(4,759)	(3,431)
Net increase in cash and cash equivalents	(17,949)	7,644
Effect of exchange rate changes on cash		(119)
Cash and cash equivalents at beginning of period	41,441	32,906
Cash and cash equivalents at end of period	$ 23,492	$ 40,431