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Long-Term Debt - Other - Additional Information (Detail) - Promissory Note - Tremont - USD ($)
$ in Millions
1 Months Ended 3 Months Ended 12 Months Ended
Jan. 31, 2020
Mar. 31, 2018
Dec. 31, 2019
Dec. 31, 2018
Debt Instrument [Line Items]        
Interest rate     3.00%  
Principal prepayments of note   $ 2.2 $ 7.4 $ 3.7
Principal amount of promissory note     $ 19.1  
Debt instrument maturity date     Dec. 31, 2023  
Subsequent Event        
Debt Instrument [Line Items]        
Principal prepayments of note $ 1.5