SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
Feb. 29, 2016	Nov. 30, 2015	Aug. 31, 2015	May. 31, 2015	Feb. 28, 2015	Nov. 30, 2014	Aug. 31, 2014	May. 31, 2014	Feb. 29, 2016	Feb. 28, 2015	Feb. 28, 2014
SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED)
Sales revenue, net	$ 385,724	$ 445,503	$ 369,129	$ 345,345	$ 377,730	$ 435,674	$ 319,949	$ 311,778	$ 1,545,701	$ 1,445,131	$ 1,317,153
Gross Profit	162,157	182,524	148,005	143,319	164,884	181,411	133,744	119,520	636,005	599,559	516,703
Asset Impairment Charges	3,000			3,000				9,000	6,000	9,000	12,049
Net Income	$ 9,588	$ 46,778	$ 24,452	$ 20,410	$ 40,550	$ 55,377	$ 18,839	$ 16,398	$ 101,228	$ 131,164	$ 86,248
Earnings per share:
Basic (in dollars per share)	$ 0.34	$ 1.66	$ 0.86	$ 0.72	$ 1.42	$ 1.95	$ 0.66	$ 0.56	$ 3.58	$ 4.59	$ 2.69
Diluted (in dollars per share)	$ 0.34	$ 1.63	$ 0.84	$ 0.70	$ 1.40	$ 1.92	$ 0.65	$ 0.55	$ 3.52	$ 4.52	$ 2.66

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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