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Earnings per Share/Limited Partner Unit - Additional Information (Detail) - shares |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | ---
Dec. 16, 2019 | Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Dilutive Restricted Shares |  |  |  |  |
Limited Partners Capital Account [Line Items] |  |  |  |  |
Weighted average number shares |  | 98,306 |  | 76,198 |
Dilutive Restricted Units |  |  |  |  |
Limited Partners Capital Account [Line Items] |  |  |  |  |
Weighted average number shares |  |  | 140,197 |  | 135,060
Hess and GIP | Class A Shares |  |  |  |  |
Limited Partners Capital Account [Line Items] |  |  |  |  |
Percentage of income tax expense attributed to earnings of Class A Shares | 100.00% |  |  |  |
Conversion of Class B units and Class B shares into Class A shares | 100.00% |  |  |  |

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