Condensed Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Feb. 28, 2013	Feb. 29, 2012
Cash flows from operating activities:
Net income	$ 16,362	$ 19,519
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	43,422	40,551
Remeasurement loss on foreign currency	135	104
Provision for losses on accounts receivable	360	130
Gain on sale of rental and lease equipment	(8,785)	(7,578)
Gain on bargain purchase, net of deferred taxes		(3,435)
Stock compensation expense	983	1,057
Excess tax benefit for share based compensation	(247)	(89)
Deferred income taxes	(637)	7,594
Changes in operating assets and liabilities, net of effect of acquisitions:
Accounts receivable	(315)	(1,686)
Other assets	(4,559)	(1,023)
Accounts payable	620	(1,140)
Accrued expenses	1,188	658
Deferred revenue	(543)	27
Net cash provided by operating activities	47,984	54,689
Cash flows from investing activities:
Proceeds from sale of rental and lease equipment	21,665	17,114
Cash paid for acquisition		(10,572)
Payments for purchase of rental and lease equipment	(48,794)	(78,703)
Payments for purchase of other property	(803)	(642)
Net cash used in investing activities	(27,932)	(72,803)
Cash flows from financing activities:
Borrowings under bank line of credit	31,500	1,000
Payments under bank line of credit	(15,000)	(1,000)
Minimum tax withholdings on share based compensation	(36)	(47)
Excess tax benefit for share based compensation	247	89
Payment of dividends	(39,003)	(14,480)
Net cash used in financing activities	(22,292)	(14,438)
Effect of exchange rate changes on cash	(345)	(11)
Net decrease in cash and cash equivalents	(2,585)	(32,563)
Cash and cash equivalents at beginning of period	9,290	41,441
Cash and cash equivalents at end of period	$ 6,705	$ 8,878