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FAIR VALUE MEASUREMENTS - Rollforward on Recurring Basis (Detail) - Fair Value, Recurring [Member] - USD ($)
$ in Millions
3 Months Ended 12 Months Ended
Mar. 31, 2021
Dec. 31, 2020
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Balance at beginning of period $ 24 $ 3
Purchases, issuances, sales and settlements:    
Issuances 10 24
Settlements (24) (3)
Balance at end of period 10 24
Interest Rate Lock Commitments [Member]    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Balance at beginning of period 24 3
Purchases, issuances, sales and settlements:    
Issuances 10 24
Settlements (24) (3)
Balance at end of period $ 10 $ 24