XML 129 R66.htm IDEA: XBRL DOCUMENT v3.20.4
Business Acquisitions - Intangible Assets Recorded in Connection with the Acquisition (Details) - The Navigators Group, Inc. [Member] - USD ($)
$ in Millions
May 23, 2019
Dec. 31, 2020
Business Acquisition [Line Items]    
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles $ 499  
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Indefinite-Lived Intangible Assets 81  
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill $ 580 $ 580
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life 10 years  
Lloyd's Syndicate Capacity [Member]    
Business Acquisition [Line Items]    
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Indefinite-Lived Intangible Assets $ 66  
License [Member]    
Business Acquisition [Line Items]    
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Indefinite-Lived Intangible Assets 15  
Value of in-force contracts [1]    
Business Acquisition [Line Items]    
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles $ 180  
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life 1 year  
Distribution relationships [Member]    
Business Acquisition [Line Items]    
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles $ 302  
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life 15 years  
Trade Names [Member]    
Business Acquisition [Line Items]    
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles $ 17  
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life 10 years