Earnings Per Share ("EPS") - Additional Information (Detail) - USD ($) $ in Millions |
3 Months Ended | |
|---|---|---|
Mar. 31, 2018 |
Mar. 31, 2017 |
|
| Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | ||
| Adjustments to net income (loss) for calculating basic EPS | $ 0 | $ 0 |
| Adjustments to net income (loss) for calculating diluted EPS | $ 0 | $ 0 |
| Restricted Stock And Performance Based Equity Awards [Member] | Outstanding Options [Member] | ||
| Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | ||
| Outstanding awards and options not included in diluted earnings per share | 122,678 | 1,019,185 |