v3.26.3
Fair Value Disclosures - Quantitative Information about Recurring Level 3 Fair Value Measurements (Details)
$ in Millions
 9 Months Ended 12 Months Ended
Sep. 30, 2026
USD ($)
Dec. 31, 2025
USD ($)
Mortgage Loans [Abstract]    
Mortgage loans FVO held-for-investment $ 6,298 $ 7,005
Other assets, fair value 6,964 6,421
Fair Value, Measurements, Recurring    
Mortgage Loans [Abstract]    
Mortgage loans FVO held-for-investment 6,298 7,005
Other assets, fair value 6,964 6,421
Total Assets carried at fair value on a recurring basis 91,429 98,838
Liabilities [Abstract]    
Total liabilities carried at fair value on a recurring basis 7,818 6,817
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3    
Mortgage Loans [Abstract]    
Mortgage loans FVO held-for-investment 1,253 1,418
Other assets, fair value 4,262 5,029
Total Assets carried at fair value on a recurring basis 8,406 9,933
Liabilities [Abstract]    
Total liabilities carried at fair value on a recurring basis 772 155
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 | Discounted Cash Flows    
Mortgage Loans [Abstract]    
Other assets, fair value 3,672 4,424
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 | Price    
Assets [Abstract]    
Debt Securities 2,125 2,532
Mortgage Loans [Abstract]    
Mortgage loans FVO held-for-investment 1,253 1,418
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 | Other Valuation Techniques    
Assets [Abstract]    
Debt Securities 766 954
Mortgage Loans [Abstract]    
Other assets, fair value $ 590 $ 605
Fair Value, Measurements, Recurring | Investments securities | Fair Value, Inputs, Level 3 | Weighted Average | Price    
Fair Value Measurement Inputs and Valuation Techniques [Abstract]    
External Pricing Source(s) 70.9 82.1
Fair Value, Measurements, Recurring | Investments securities | Fair Value, Inputs, Level 3 | Minimum | Price    
Fair Value Measurement Inputs and Valuation Techniques [Abstract]    
External Pricing Source(s) 0.0 0.0
Fair Value, Measurements, Recurring | Investments securities | Fair Value, Inputs, Level 3 | Maximum | Price    
Fair Value Measurement Inputs and Valuation Techniques [Abstract]    
External Pricing Source(s) 2,541.8 3,520.6
Fair Value, Measurements, Recurring | Mortgage loans held-for-investment | Fair Value, Inputs, Level 3 | Weighted Average | Price    
Fair Value Measurement Inputs and Valuation Techniques [Abstract]    
External Pricing Source(s) 84.1 89.0
Fair Value, Measurements, Recurring | Mortgage loans held-for-investment | Fair Value, Inputs, Level 3 | Minimum | Price    
Fair Value Measurement Inputs and Valuation Techniques [Abstract]    
External Pricing Source(s) 25.3 48.4
Fair Value, Measurements, Recurring | Mortgage loans held-for-investment | Fair Value, Inputs, Level 3 | Maximum | Price    
Fair Value Measurement Inputs and Valuation Techniques [Abstract]    
External Pricing Source(s) 101.5 105.8
Fair Value, Measurements, Recurring | Other Asset Fair Value | Fair Value, Inputs, Level 3 | Weighted Average | Discounted Cash Flows    
Fair Value Measurement Inputs and Valuation Techniques [Abstract]    
OAS 0.51% 0.50%
Fair Value, Measurements, Recurring | Other Asset Fair Value | Fair Value, Inputs, Level 3 | Minimum | Discounted Cash Flows    
Fair Value Measurement Inputs and Valuation Techniques [Abstract]    
OAS 0.20% 0.17%
Fair Value, Measurements, Recurring | Other Asset Fair Value | Fair Value, Inputs, Level 3 | Maximum | Discounted Cash Flows    
Fair Value Measurement Inputs and Valuation Techniques [Abstract]    
OAS 16.16% 88.50%