CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($)	3 Months Ended
	Apr. 30, 2021	Apr. 30, 2020
Statement of Comprehensive Income [Abstract]
Net (loss) gain on derivative instruments, tax expense (benefit)	$ (1,700,000)	$ (400,000)
Change in net unrealized gain (loss) on available-for-sale securities, tax expense (benefit)	0	100,000
Change in defined pension items, tax expense (benefit)	0	0
Net change in cumulative foreign currency translation (loss) gain, tax expense (benefit)	$ (1,800,000)	$ 0