Quarterly Financial Information, Unaudited (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Feb. 29, 2020	Nov. 30, 2019	Aug. 31, 2019	May 31, 2019	Feb. 28, 2019	Nov. 30, 2018	Aug. 31, 2018	May 31, 2018	Feb. 29, 2020	Feb. 28, 2019	Feb. 28, 2018
Quarterly Financial Information Disclosure [Abstract]
Revenues	$ 245,365	$ 291,139	$ 236,190	$ 289,123	$ 202,548	$ 239,516	$ 222,787	$ 262,236	$ 1,061,817	$ 927,087	$ 810,430
Gross profit	51,104	67,331	52,686	66,107	43,257	49,755	46,904	58,705	237,228	198,621	160,309
Net income	$ (10,643)	$ 22,035	$ 15,558	$ 21,284	$ 8,851	$ 15,395	$ 11,244	$ 15,718	$ 48,234	$ 51,208	$ 45,169
Basic earnings per common share (usd per share)	$ (0.41)	$ 0.84	$ 0.59	$ 0.81	$ 0.34	$ 0.59	$ 0.43	$ 0.60	$ 1.84	$ 1.97	$ 1.74
Diluted earnings per common share (usd per share)	$ (0.41)	$ 0.84	$ 0.59	$ 0.81	$ 0.34	$ 0.59	$ 0.43	$ 0.60	$ 1.84	$ 1.96	$ 1.73
Loss on disposal of business	$ (18,600)								$ (18,632)	$ 0	$ 0
Gain (Loss) on Disposition of Assets	$ 9,200								$ (9,157)	$ (810)	$ (10,834)