XML 70 R59.htm IDEA: XBRL DOCUMENT v3.19.2
Commitments, contingencies, and guarantees Commitments, Contingencies, And Guarantees (Transactions accounted for as secured borrowings) (Details) - USD ($)
$ in Millions
Jun. 30, 2019
Dec. 31, 2018
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]    
Securities lending collateral $ 1,727 $ 1,926
Securities lending payable 1,727 1,926
Cash [Member] | Overnight and Continuous [Member]    
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]    
Securities lending collateral 583 756
U.S. Treasury and agency | Overnight and Continuous [Member]    
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]    
Securities lending collateral 117 64
Foreign [Member] | Overnight and Continuous [Member]    
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]    
Securities lending collateral 700 795
Corporate securities | Overnight and Continuous [Member]    
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]    
Securities lending collateral 50 15
Mortgage-backed securities | Overnight and Continuous [Member]    
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]    
Securities lending collateral 51 45
Equity Securities [Member] | Overnight and Continuous [Member]    
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]    
Securities lending collateral $ 226 $ 251