Income Taxes - Components of Income before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2020
Income Tax Disclosure [Abstract]
United States	$ 487,962	$ 378,042	$ 305,339
Foreign	24,349	15,951	8,358
Income before income taxes	$ 512,311	$ 393,993	$ 313,697

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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