Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	May 31, 2013		May 31, 2012		May 31, 2011
Revenues:
Rentals and leases	$ 136,591		$ 129,737		$ 118,062
Sales of equipment and other revenues	112,140		118,817		110,667
Total revenues	248,731	[1]	248,554	[1]	228,729	[1]
Operating expenses:
Depreciation of rental and lease equipment	56,795		53,651		47,922
Costs of rentals and leases, excluding depreciation	17,788		17,320		16,397
Costs of sales of equipment and other revenues	80,894		88,247		80,263
Selling, general and administrative expenses	56,543		53,250		47,412
Total operating expenses	212,020		212,468		191,994
Operating profit	36,711		36,086		36,735
Gain on bargain purchase, net of deferred taxes			3,435		202
Interest income, net	402		484		352
Income before income taxes	37,113		40,005		37,289
Income tax provision	14,359		14,233		13,533
Net income	$ 22,754		$ 25,772		$ 23,756
Earnings per share:
Basic	$ 0.94		$ 1.07		$ 0.99
Diluted	$ 0.94		$ 1.07		$ 0.99
Shares used in per share calculation:
Basic	24,226		23,983		23,974
Diluted	24,269		24,152		24,072
Cash dividend declared per share	$ 1.80		$ 0.80		$ 0.60

[1] Revenues by country are based on the location of shipping destination, whether the order originates in the U.S. parent or a foreign subsidiary.