Revenue Contract Asset and Contract Liabilities balances (Details) - USD ($) $ in Thousands		3 Months Ended
		Apr. 30, 2018	Jan. 31, 2018
Capitalized Contract Cost [Line Items]
Increase (Decrease) in Contract Assets		$ (395)
Increase (Decrease) in Contract Liabilities		(903)
Short-term Contract with Customer [Member]
Capitalized Contract Cost [Line Items]
Contract with Customer, Asset, Gross	[1]	2,724	$ 3,119
Increase (Decrease) in Contract Assets		$ (395)
Increase (decrease) in contract assets with customers, percentage	[1]	(12.70%)
Contract with Customer, Liability, Current	[2]	$ 987	$ 1,890
Increase (Decrease) in Contract Liabilities		$ (903)
Increase (decrease) in contract liabilities with customers, percentage	[2]	(47.80%)

[1] Contract assets are reported in "Accounts receivable, net" in the Consolidated Balance Sheet.

[2] Contract liabilities are reported in "Other current liabilities" in the Consolidated Balance Sheet.