Summary of Business and Significant Accounting Policies - Accounts Receivable Allowance For Credit Loss Rollforward (Details) $ in Thousands	12 Months Ended
	Jan. 31, 2021 USD ($)
Allowance for Doubtful Accounts Receivable [Roll Forward]
Allowance for Doubtful Accounts Receivable, Beginning Balance	$ 5,150
Provision for credit losses	25,651
Write-offs	(10,301)
Allowance for Doubtful Accounts Receivable, Ending Balance	$ 20,500