Condensed Consolidated Statements of Operations (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Nov. 30, 2012	Nov. 30, 2011	Nov. 30, 2012	Nov. 30, 2011
Revenues:
Rentals and leases	$ 34,575	$ 32,912	$ 68,240	$ 64,221
Sales of equipment and other revenues	30,617	28,731	55,453	56,072
Total revenues	65,192	61,643	123,693	120,293
Operating expenses:
Depreciation of rental and lease equipment	14,082	13,374	28,140	25,901
Costs of rental and lease, excluding depreciation	4,558	4,394	8,930	8,773
Costs of sales of equipment and other revenues	22,164	21,287	40,213	41,291
Selling, general and administrative expenses	14,068	13,149	27,845	26,269
Total operating expenses	54,872	52,204	105,128	102,234
Operating profit	10,320	9,439	18,565	18,059
Gain on bargain purchase, net of deferred taxes		188		3,382
Interest income, net	137	108	283	207
Income before income taxes	10,457	9,735	18,848	21,648
Income tax provision	4,218	3,716	7,523	7,124
Net income	$ 6,239	$ 6,019	$ 11,325	$ 14,524
Earnings per share:
Basic	$ 0.26	$ 0.25	$ 0.47	$ 0.61
Diluted	$ 0.26	$ 0.25	$ 0.47	$ 0.60
Shares used in per share calculation:
Basic	23,988	23,981	23,994	23,981
Diluted	24,225	24,149	24,221	24,139
Cash dividend paid per common share	$ 0.20	$ 0.20	$ 0.20	$ 0.20