XML 170 R137.htm IDEA: XBRL DOCUMENT v3.20.4
FAIR VALUE MEASUREMENTS - Schedule of Level 3 Instruments (Details) - Level 3 - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation    
Net unrealized gain (losses) in other comprehensive income $ 323 $ 404
Investment securities    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation    
Balance at beginning of period 5,210 4,013
Net realized/unrealized gains (losses) 357 399
Purchases 1,301 2,159
Sales & Settlements (958) (1,308)
Transfers into Level 3 2 0
Transfers out of Level 3 (45) (53)
Balance at end of period 5,866 5,210
U.S. corporate    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation    
Purchases   $ 975
Mortgage and asset-backed    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation    
Purchases $ 745