Annual report pursuant to Section 13 and 15(d)

FAIR VALUES OF ASSETS AND LIABILITIES - Significant Unobservable Level 3 Inputs (Details)

v3.20.4
FAIR VALUES OF ASSETS AND LIABILITIES - Significant Unobservable Level 3 Inputs (Details)
$ in Millions
Dec. 31, 2020
USD ($)
Dec. 31, 2019
USD ($)
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Derivative assets gross $ 1,946 $ 856
Recurring    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
MSRs 210 7
Available-for-sale securities 16,485 14,149
Recurring | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
MSRs 210 7
Derivative assets gross 43 8
Available-for-sale securities 2,970 3,049
Nonrecurring    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Collateral-dependent loans   26
Nonrecurring | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
MSRs   206
Fair Value    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Available-for-sale securities 16,485 14,149
Fair Value | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Available-for-sale securities 2,970 3,049
Fair Value | Nonrecurring    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Collateral-dependent loans 144  
Fair Value | Nonrecurring | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Collateral-dependent loans 144  
Municipal securities | Recurring    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Available-for-sale securities 3,004 3,055
Municipal securities | Recurring | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Available-for-sale securities 2,951 2,999
Asset-backed securities | Recurring    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Available-for-sale securities 192 579
Asset-backed securities | Recurring | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Available-for-sale securities 10 48
Residential MBS | Recurring    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Available-for-sale securities 7,935 4,222
Residential MBS | Recurring | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Available-for-sale securities $ 0 $ 0
Residential MBS | Measurement Input, Constant Prepayment Rate | Recurring | Maximum | Valuation Technique, Discounted Cash Flow | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Servicing Asset, Measurement Input 0.24 0.26
Residential MBS | Measurement Input, Constant Prepayment Rate | Recurring | Minimum | Valuation Technique, Discounted Cash Flow | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Servicing Asset, Measurement Input 0.08 0
Residential MBS | Measurement Input, Constant Prepayment Rate | Recurring | Weighted Average | Valuation Technique, Discounted Cash Flow | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Servicing Asset, Measurement Input 0.17 0.08
Residential MBS | Measurement Input, Constant Prepayment Rate | Nonrecurring | Maximum | Valuation Technique, Discounted Cash Flow | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Servicing Asset, Measurement Input   0.31
Residential MBS | Measurement Input, Constant Prepayment Rate | Nonrecurring | Minimum | Valuation Technique, Discounted Cash Flow | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Servicing Asset, Measurement Input   0.10
Residential MBS | Measurement Input, Constant Prepayment Rate | Nonrecurring | Weighted Average | Valuation Technique, Discounted Cash Flow | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Servicing Asset, Measurement Input   0.12
Residential MBS | Measurement Input, Option Adjusted Spread | Recurring | Maximum | Valuation Technique, Discounted Cash Flow | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Servicing Asset, Measurement Input 0.11 0.11
Residential MBS | Measurement Input, Option Adjusted Spread | Recurring | Minimum | Valuation Technique, Discounted Cash Flow | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Servicing Asset, Measurement Input 0.04 0.05
Residential MBS | Measurement Input, Option Adjusted Spread | Recurring | Weighted Average | Valuation Technique, Discounted Cash Flow | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Servicing Asset, Measurement Input 0.05 0.08
Residential MBS | Measurement Input, Option Adjusted Spread | Nonrecurring | Maximum | Valuation Technique, Discounted Cash Flow | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Servicing Asset, Measurement Input   0.11
Residential MBS | Measurement Input, Option Adjusted Spread | Nonrecurring | Minimum | Valuation Technique, Discounted Cash Flow | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Servicing Asset, Measurement Input   0.05
Residential MBS | Measurement Input, Option Adjusted Spread | Nonrecurring | Weighted Average | Valuation Technique, Discounted Cash Flow | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Servicing Asset, Measurement Input   0.09
Derivative Assets | Measurement Input, Net Market Price | Recurring | Maximum | Valuation Technique, Consensus Pricing Model | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Derivative Asset, Measurement Input 0.11 0.11
Derivative Assets | Measurement Input, Net Market Price | Recurring | Minimum | Valuation Technique, Consensus Pricing Model | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Derivative Asset, Measurement Input (0.04) (0.02)
Loans held for investment, Measurement Input 0.03  
Derivative Assets | Measurement Input, Net Market Price | Recurring | Weighted Average | Valuation Technique, Consensus Pricing Model | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Derivative Asset, Measurement Input   0.02
Derivative Assets | Measurement Input, Estimated Pull Thru | Recurring | Maximum | Valuation Technique, Consensus Pricing Model | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Derivative Asset, Measurement Input 1 1
Derivative Assets | Measurement Input, Estimated Pull Thru | Recurring | Minimum | Consensus Pricing | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Loans held for investment, Measurement Input 0.88  
Derivative Assets | Measurement Input, Estimated Pull Thru | Recurring | Minimum | Valuation Technique, Consensus Pricing Model | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Derivative Asset, Measurement Input 0.01 0.02
Derivative Assets | Measurement Input, Estimated Pull Thru | Recurring | Weighted Average | Valuation Technique, Consensus Pricing Model | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Derivative Asset, Measurement Input   0.91
Corporate obligations | Recurring    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Available-for-sale securities $ 445 $ 51
Corporate obligations | Recurring | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Available-for-sale securities $ 0 $ 0
Corporate obligations | Measurement Input, Discount Rate | Recurring | Maximum | Valuation Technique, Discounted Cash Flow | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Debt Securities, Available-for-sale, Measurement Input 0.01 0.03
Corporate obligations | Measurement Input, Discount Rate | Recurring | Minimum | Valuation Technique, Discounted Cash Flow | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Debt Securities, Available-for-sale, Measurement Input 0 0.02
Corporate obligations | Measurement Input, Discount Rate | Recurring | Weighted Average | Valuation Technique, Discounted Cash Flow | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Debt Securities, Available-for-sale, Measurement Input 0.01 0.02
Corporate obligations | Measurement Input, Default Rate | Recurring | Maximum | Valuation Technique, Discounted Cash Flow | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Debt Securities, Available-for-sale, Measurement Input 0.39 0.39
Corporate obligations | Measurement Input, Default Rate | Recurring | Minimum | Valuation Technique, Discounted Cash Flow | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Debt Securities, Available-for-sale, Measurement Input 0 0
Corporate obligations | Measurement Input, Default Rate | Recurring | Weighted Average | Valuation Technique, Discounted Cash Flow | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Debt Securities, Available-for-sale, Measurement Input 0.04 0.04
Corporate obligations | Measurement Input, Loss Severity | Recurring | Maximum | Valuation Technique, Discounted Cash Flow | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Debt Securities, Available-for-sale, Measurement Input 0.80 0.80
Corporate obligations | Measurement Input, Loss Severity | Recurring | Minimum | Valuation Technique, Discounted Cash Flow | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Debt Securities, Available-for-sale, Measurement Input 0.05 0.05
Corporate obligations | Measurement Input, Loss Severity | Recurring | Weighted Average | Valuation Technique, Discounted Cash Flow | Level 3    
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]    
Debt Securities, Available-for-sale, Measurement Input 0.25 0.24