v3.26.3
Fair Value Measurement - Recurring Fair Value Measurements (Details) - USD ($)
$ in Millions
Sep. 30, 2026
Dec. 31, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value [1] $ 4,356 $ 2,348
Fair Value, Measurements, Recurring    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Assets measured at fair value, Other [2],[3] 16 22
Total [2] 4,372 2,370
Fair Value, Measurements, Recurring | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Assets measured at fair value, Other [3] 12 15
Total 12 15
Fair Value, Measurements, Recurring | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Assets measured at fair value, Other [3] 0 0
Total 4,298 2,304
Fair Value, Measurements, Recurring | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Assets measured at fair value, Other [3] 4 7
Total 62 51
U.S. government and federal agency    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value 3,394 1,492
U.S. government and federal agency | Fair Value, Measurements, Recurring    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value [2] 3,394 1,492
U.S. government and federal agency | Fair Value, Measurements, Recurring | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value 0 0
U.S. government and federal agency | Fair Value, Measurements, Recurring | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value 3,394 1,492
U.S. government and federal agency | Fair Value, Measurements, Recurring | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value 0 0
State and municipal    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value 50 35
State and municipal | Fair Value, Measurements, Recurring    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value [2] 50 35
State and municipal | Fair Value, Measurements, Recurring | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value 0 0
State and municipal | Fair Value, Measurements, Recurring | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value 0 0
State and municipal | Fair Value, Measurements, Recurring | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value 50 35
Residential mortgage-backed    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value [4] 309 297
Residential mortgage-backed | Fair Value, Measurements, Recurring    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value [2] 309 297
Residential mortgage-backed | Fair Value, Measurements, Recurring | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value 0 0
Residential mortgage-backed | Fair Value, Measurements, Recurring | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value 309 297
Residential mortgage-backed | Fair Value, Measurements, Recurring | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value 0 0
Asset-backed    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value [5] 595 515
Asset-backed | Fair Value, Measurements, Recurring    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value [2] 595 515
Asset-backed | Fair Value, Measurements, Recurring | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value 0 0
Asset-backed | Fair Value, Measurements, Recurring | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value 595 515
Asset-backed | Fair Value, Measurements, Recurring | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value 0 0
Other Debt Obligations    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value 8 9
Other Debt Obligations | Fair Value, Measurements, Recurring    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value [2] 8 9
Other Debt Obligations | Fair Value, Measurements, Recurring | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value 0 0
Other Debt Obligations | Fair Value, Measurements, Recurring | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value 0 0
Other Debt Obligations | Fair Value, Measurements, Recurring | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Estimated fair value $ 8 $ 9
[1] At September 30, 2026 and December 31, 2025, the estimated fair value of debt securities pledged by the Bank as collateral to the Federal Reserve to secure Federal Reserve discount window advances was $288 million and $470 million, respectively.
[2] For the nine months ended September 30, 2026 and 2025, there were no fair value measurements transferred between levels and changes in our Level 3 assets were not material.
[3] Other is primarily comprised of equity investments measured at fair value, which are included in Other assets in our Condensed Consolidated Statements of Financial Position
[4] Our residential mortgage-backed securities have been issued by government-sponsored entities and are collateralized by U.S. mortgages.
[5]     Our asset-backed securities are collateralized by credit card and auto loans.