Debt (Existing Credit Facility) (Detail) - Predecessor - USD ($) |
3 Months Ended | 12 Months Ended | ||
|---|---|---|---|---|
Mar. 21, 2017 |
Sep. 30, 2016 |
Dec. 31, 2016 |
Mar. 31, 2016 |
|
| Line Of Credit Facility [Line Items] | ||||
| Amount utilized to offset outstanding borrowings under credit facility | $ 103,560,000 | $ 103,560,000 | ||
| Existing Credit Facility | ||||
| Line Of Credit Facility [Line Items] | ||||
| Borrowing base amount | $ 550,000,000 | |||
| Availability under the facility | 0 | |||
| Proceeds from additional borrowing credit facility | 181,000,000 | |||
| Amount utilized to offset outstanding borrowings under credit facility | $ 103,560,000 | |||
| Weighted average interest rate | 5.25% | |||
| Additional interest rate on outstanding amounts in event of default waived | 2.00% | |||
| Repayments of debt | $ 444,440,000 |