Business And Summary Of Significant Accounting Policies (Details) - USD ($) $ in Millions |
3 Months Ended | ||
|---|---|---|---|
Apr. 30, 2018 |
Apr. 30, 2017 |
Jan. 31, 2018 |
|
| Accounting Policies [Abstract] | |||
| Accounts receivable sold | $ 627.7 | $ 687.2 | |
| Discount fees on sale of accounts receivable | $ 2.7 | $ 1.7 | |