Investment in Equity Interests - Equity Method Investments (Details) - USD ($) $ in Millions |
3 Months Ended | |
|---|---|---|
Jul. 29, 2017 |
Jul. 30, 2016 |
|
| Equity Method Investments and Joint Ventures [Abstract] | ||
| Equity method investment | $ 10.6 | $ 10.1 |
| Increase in equity method investment during period | $ 0.5 |