XML 106 R89.htm IDEA: XBRL DOCUMENT v3.8.0.1
Contingencies - Narrative (Details) - USD ($)
$ in Millions
3 Months Ended
Dec. 24, 2015
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2015
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Loss Contingencies [Line Items]                
Reinsurance recoverables on asbestos and environmental reserves, net of allowance         $ 2,957 $ 2,302 $ 2,201 $ 2,227
Property and Casualty Group                
Loss Contingencies [Line Items]                
Increase in asbestos and environmental reserves   $ 89 $ 36 $ 67        
Liability for asbestos and environmental reserves         528      
Former railroad and manufacturing operations                
Loss Contingencies [Line Items]                
Increase in asbestos and environmental reserves   $ 24 $ 5 $ 12        
American Premier and its subsidiaries                
Loss Contingencies [Line Items]                
Liability for environmental and other claims         81      
GAFRI                
Loss Contingencies [Line Items]                
Liability for environmental and other claims         8      
Run-off long-term care insurance business                
Loss Contingencies [Line Items]                
Contingent capital support agreement term 5 years              
A&E reserves | Property and Casualty Group                
Loss Contingencies [Line Items]                
Reinsurance recoverables on asbestos and environmental reserves, net of allowance         $ 125