Earnings Per Share - Reconciliation of Numerators and Denominators of Earnings Per Share Calculation (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	May 31, 2019	May 31, 2018
Earnings Per Share [Abstract]
Net income available to common stockholders	$ 141,120	$ 113,190
Weighted average common shares outstanding (in shares)	177,400	177,302
Incremental shares attributable to assumed vesting or exercise of outstanding equity award shares (in shares)	2,803	3,833
Dilutive effect of convertible notes (in shares)	1,554	5,686
Dilutive effect of warrants (in shares)	4,878	3,918
Diluted shares (in shares)	186,635	190,739
Diluted net income per share (in dollars per share)	$ 0.76	$ 0.59