Revenues from Rental, Lease and Sale Segment (Detail) - USD ($) $ in Thousands	3 Months Ended								6 Months Ended	12 Months Ended
	May 31, 2016	Feb. 29, 2016	Nov. 30, 2015	Aug. 31, 2015	May 31, 2015	Feb. 28, 2015	Nov. 30, 2014	Aug. 31, 2014	Nov. 30, 2014	May 31, 2016	May 31, 2015	May 31, 2014
Revenue from External Customer [Line Items]
Rentals and leases										$ 123,785	$ 129,255	$ 137,417
Sales of equipment and other revenues										51,548	109,074	103,720
Total revenues	$ 39,182	$ 39,498	$ 43,310	$ 53,343	$ 60,413	$ 56,342	$ 59,703	$ 61,871	$ 238,329	175,333	238,329	241,137
T&M equipment
Revenue from External Customer [Line Items]
Rentals and leases										105,850	111,327	120,629
Sales of equipment and other revenues										49,518	107,270	101,898
Total revenues										155,368	218,597	222,527
DP equipment
Revenue from External Customer [Line Items]
Rentals and leases										17,935	17,928	16,788
Sales of equipment and other revenues										2,030	1,804	1,822
Total revenues										$ 19,965	$ 19,732	$ 18,610