Restructuring Provision - Summary of Rollforward of Provision Related Corporate Initiatives, Including Provision Associated with Restructuring Plan (Parenthetical) (Details) - USD ($) $ in Thousands	Jul. 31, 2020	Jan. 31, 2020	Jul. 31, 2019
Restructuring Cost And Reserve [Line Items]
Accrued payroll and benefits	$ 12,431	$ 6,302	$ 7,333
Capital in excess of par value	211,628	$ 208,473	$ 205,117
Severance and Employee Related
Restructuring Cost And Reserve [Line Items]
Accrued payroll and benefits	5,900
Capital in excess of par value	$ 400