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Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)
$ in Millions
3 Months Ended
Mar. 31, 2020
Mar. 31, 2019
Dec. 31, 2019
Significant Accounting Policies [Line Items]      
Amortization expense for the deferred costs $ 9.0 $ 7.7  
Other Assets [Member]      
Significant Accounting Policies [Line Items]      
Deferred costs $ 101.0   $ 106.4