| Debt Securities |
Debt Securities The following tables present the amortized cost, gross unrealized gains and losses, and estimated fair values of debt securities as of the dates presented: | | | | | | | | | | | | | | | | | | | | | | | | | March 31, 2026 | | (in millions) | Amortized Cost | | Gross Unrealized Gains | | Gross Unrealized Losses | | Fair Value | | Available for sale: | | | | | | | | | U.S. Treasury and agencies | $ | 1,227 | | | $ | 3 | | | $ | (40) | | | $ | 1,190 | | | Obligations of states and political subdivisions | 1,577 | | | 26 | | | (20) | | | 1,583 | | Mortgage-backed securities and collateralized mortgage obligations | 8,458 | | | 34 | | | (350) | | | 8,142 | | | Total available for sale securities | $ | 11,262 | | | $ | 63 | | | $ | (410) | | | $ | 10,915 | | | Held to maturity: | | | | | | | | Corporate and other securities | $ | 18 | | | $ | — | | | $ | — | | | $ | 18 | | | Total held to maturity securities | $ | 18 | | | $ | — | | | $ | — | | | $ | 18 | |
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| December 31, 2025 | (in millions) | Amortized Cost | | Gross Unrealized Gains | | Gross Unrealized Losses | | Fair Value | | Available for sale: | | | | | | | | | U.S. Treasury and agencies | $ | 1,332 | | | $ | 6 | | | $ | (38) | | | $ | 1,300 | | | Obligations of states and political subdivisions | 1,597 | | | 47 | | | (15) | | | 1,629 | | Mortgage-backed securities and collateralized mortgage obligations | 8,447 | | | 63 | | | (327) | | | 8,183 | | | Total available for sale securities | $ | 11,376 | | | $ | 116 | | | $ | (380) | | | $ | 11,112 | | | Held to maturity: | | | | | | | | Corporate and other securities | $ | 18 | | | $ | 1 | | | $ | — | | | $ | 19 | | | Total held to maturity securities | $ | 18 | | | $ | 1 | | | $ | — | | | $ | 19 | |
The Company elected to exclude accrued interest receivable from the amortized cost basis of debt securities disclosed throughout this note. Accrued interest on investment securities totaled $43 million and $46 million as of March 31, 2026 and December 31, 2025, respectively, and is included in other assets on the Consolidated Balance Sheets. There were no gross realized gains or losses from sales of AFS debt securities for both the three months ended March 31, 2026 and 2025.
The following tables present debt securities that were in an unrealized loss position as of the dates presented, categorized by the length of time individual securities have been in an unrealized loss position: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| March 31, 2026 | | Less than 12 Months | | 12 Months or Longer | | Total | (in millions) | Fair Value | | Gross Unrealized Losses | | Fair Value | | Gross Unrealized Losses | | Fair Value | | Gross Unrealized Losses | | Available for sale: | | | | | | | | | | | | | U.S. Treasury and agencies | $ | 100 | | | $ | (1) | | | $ | 775 | | | $ | (39) | | | $ | 875 | | | $ | (40) | | Obligations of states and political subdivisions | 434 | | | (4) | | | 151 | | | (16) | | | 585 | | | (20) | | Mortgage-backed securities and collateralized mortgage obligations | 2,889 | | | (31) | | | 1,962 | | | (319) | | | 4,851 | | | (350) | | | Total temporarily impaired securities | $ | 3,423 | | | $ | (36) | | | $ | 2,888 | | | $ | (374) | | | $ | 6,311 | | | $ | (410) | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
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| December 31, 2025 | | Less than 12 Months | | 12 Months or Longer | | Total | (in millions) | Fair Value | | Gross Unrealized Losses | | Fair Value | | Gross Unrealized Losses | | Fair Value | | Gross Unrealized Losses | | Available for sale: | | | | | | | | | | | | | U.S. Treasury and agencies | $ | 50 | | | $ | — | | | $ | 778 | | | $ | (38) | | | $ | 828 | | | $ | (38) | | Obligations of states and political subdivisions | 29 | | | — | | | 219 | | | (15) | | | 248 | | | (15) | | Mortgage-backed securities and collateralized mortgage obligations | 1,287 | | | (9) | | | 2,374 | | | (318) | | | 3,661 | | | (327) | | | Total temporarily impaired securities | $ | 1,366 | | | $ | (9) | | | $ | 3,371 | | | $ | (371) | | | $ | 4,737 | | | $ | (380) | |
The number of individual debt securities in an unrealized loss position in the tables above increased to 811 as of March 31, 2026, as compared to 592 at December 31, 2025. The unrealized losses in the Company's debt securities portfolio are primarily attributable to changes in market interest rates or the widening of market spreads subsequent to the initial purchase of these securities, rather than deterioration in the credit quality of the issuers. Management actively monitors the published credit ratings of the issuers of the debt securities for any material changes in rating or outlooks. As the decline in fair value of the debt securities is attributable to interest rate movements and market spread volatility and not credit related factors, no ACL has been recorded on these debt securities as of March 31, 2026.
The following table presents the contractual maturities of the Company's debt securities as of March 31, 2026. Actual maturities may differ from contractual maturities due to the potential for early calls, prepayments, or principal repayments, with or without call or prepayment penalties. | | | | | | | | | | | | | | | | | | | | | | | |
| Available For Sale | | Held To Maturity | (in millions) | Amortized Cost | | Fair Value | | Amortized Cost | | Fair Value | | Due within one year | $ | 419 | | | $ | 418 | | | $ | — | | | $ | — | | | Due after one year through five years | 2,683 | | | 2,658 | | | — | | | — | | | Due after five years through ten years | 1,626 | | | 1,595 | | | 1 | | | 1 | | | Due after ten years | 6,534 | | | 6,244 | | | 17 | | | 17 | | | Total debt securities | $ | 11,262 | | | $ | 10,915 | | | $ | 18 | | | $ | 18 | |
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