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Consolidated Variable Interest Entities - Additional Information (Details)
12 Months Ended
Dec. 31, 2020
USD ($)
entity
Dec. 31, 2019
USD ($)
entity
Dec. 31, 2018
USD ($)
Organization Consolidation And Presentation Of Financial Statements [Abstract]      
Number of VIEs consolidated | entity 4 4  
Financial or other support to any VIEs | $ $ 0 $ 0 $ 0