Subsequent Event - Additional Information (Detail) - Subsequent Event - Drilling Equipment - Purchase and Sale Agreement $ in Millions |
1 Months Ended |
|---|---|
|
Feb. 28, 2017
USD ($)
| |
| Subsequent Event [Line Items] | |
| Purchase price of acquire assets | $ 13.0 |
| Down Payment upon Execution of Agreement | 1.3 |
| Remaining amount due under agreement | $ 11.7 |