Restructuring Provision - Summary of Rollforward of Provision Related Corporate Initiatives, Including Provision Associated with Restructuring Plan (Details) - USD ($) $ in Thousands		3 Months Ended			6 Months Ended
		Jul. 31, 2020		Apr. 30, 2020	Jul. 31, 2020
Restructuring Cost And Reserve [Line Items]
Beginning Balance		$ 7,240
Provision		7,368		$ 7,240	$ 14,608
Non-Cash Use		(1,763)			(1,763)
Cash Payments		(1,837)			(1,837)
Ending Balance		11,008		7,240	11,008
Restructuring Plan | Severance and Employee Related
Restructuring Cost And Reserve [Line Items]
Provision		6,966			6,966	[1]
Cash Payments		(1,160)			(1,160)	[1]
Ending Balance	[1]	5,806			5,806
Restructuring Plan | Other
Restructuring Cost And Reserve [Line Items]
Provision		402			402	[2]
Non-Cash Use		(198)			(198)	[2]
Cash Payments		(115)			(115)	[2]
Ending Balance	[2]	89			89
Corporate Initiative | Severance and Employee Related
Restructuring Cost And Reserve [Line Items]
Beginning Balance		936
Provision	[1]				936
Cash Payments		(395)			(395)	[1]
Ending Balance		541	[1]	936	541	[1]
Corporate Initiative | Inventory
Restructuring Cost And Reserve [Line Items]
Beginning Balance		3,507
Provision	[3]				3,507
Non-Cash Use		(47)			(47)	[3]
Ending Balance		3,460	[3]	3,507	3,460	[3]
Corporate Initiative | Accounts Receivable
Restructuring Cost And Reserve [Line Items]
Beginning Balance		1,075
Provision	[4]				1,075
Ending Balance		1,075	[4]	1,075	1,075	[4]
Corporate Initiative | Other
Restructuring Cost And Reserve [Line Items]
Beginning Balance		1,722
Provision	[2]				1,722
Non-Cash Use		(1,518)			(1,518)	[2]
Cash Payments		(167)			(167)	[2]
Ending Balance		$ 37	[2]	$ 1,722	$ 37	[2]

[1] $5.9 million included in Accrued payroll and benefits and $0.4 million included in Capital in excess of par value.

[2] Balance included in Accrued liabilities.

[3] Reserve included in Inventories.

[4] Reserve included in Trade receivable, net.