Share-Based Compensation - Unrecognized Compensation Expense and Period for Recognition (Details) $ in Millions |
9 Months Ended |
|---|---|
|
Oct. 28, 2017
USD ($)
| |
| Stock Options [Member] | |
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |
| Unrecognized share-based compensation expense | $ 2.8 |
| Period for recognition (in years) | 1 year 9 months |
| Restricted Stock Units (RSUs) [Member] | |
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |
| Unrecognized share-based compensation expense | $ 24.4 |
| Period for recognition (in years) | 1 year 11 months |