Accrued Liabilities (Details) - USD ($) $ in Millions	Jan. 31, 2017	Jan. 31, 2016
Accrued Liabilities
Accrued salaries, vacation and related benefits	$ 31.6	$ 28.7
Accrued commissions	8.7	6.2
Income taxes payable	10.3	11.4
Accrued interest	11.7	11.7
Other accrued liabilities	28.8	57.3
Total accrued liabilities	$ 91.1	$ 115.3