Accrued Liabilities (Details) - USD ($) $ in Millions	Jul. 31, 2017	Jan. 31, 2017
Accrued Liabilities
Accrued salaries, vacation and related benefits	$ 28.9	$ 31.6
Accrued commissions	6.3	8.7
Income taxes payable	13.6	10.3
Accrued interest	11.7	11.7
Other accrued liabilities	32.7	28.8
Total accrued liabilities	$ 93.2	$ 91.1