Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended
Apr. 30, 2020	Apr. 30, 2019
Income Tax Disclosure [Abstract]
Net income before provision for income taxes	$ 29,175	$ 2,530
Provision for income taxes	$ 2,100	$ 316
Effective tax rate	7.20%	12.50%

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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