Share-based Compensation - Summary of Options Vested and Expected to Vest (Details) - Non-qualified Stock Options [Member] - USD ($) $ / shares in Units, $ in Millions |
7 Months Ended | 12 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2015 |
Jun. 30, 2017 |
Jun. 30, 2016 |
Feb. 01, 2015 |
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Number of options (in shares) | 4,359,066 | 8,556,912 | 4,984,970 | |
| Weighted average exercise price (in dollars per share) | $ 3.50 | $ 6.44 | $ 4.01 | |
| Intrinsic value | $ 6.5 | $ 67.3 | $ 23.6 | |
| Weighted-average remaining contractual term | 9 years 7 months 6 days | 7 years | 7 years 8 months 12 days | |
| Predecessor [Member] | ||||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Number of options (in shares) | 0 | |||
| Weighted average exercise price (in dollars per share) | $ 0.00 | |||
| Intrinsic value | $ 0.0 | |||