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Investment Securities (Tables) | 3 Months Ended
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Mar. 31, 2026
Investment Securities [Abstract] |
Summary Investment Holdings | Investment securities consisted of the following at March 31, 2026 and December 31, 2025.
(In thousands) | March 31, 2026 | December 31, 2025
Available for sale debt securities | $ | 8,646,127 |  | $ | 9,095,513 |
Trading debt securities | 44,329 |  | 40,080 |
Equity securities: |  |
Readily determinable fair value | 46,193 |  | 47,551 |
No readily determinable fair value | 10,000 |  | 9,803 |
Other: |  |
Federal Reserve Bank stock | 54,434 |  | 35,918 |
Federal Home Loan Bank stock | 10,141 |  | 10,198 |
Private equity investments | 183,764 |  | 184,343 |
Total investment securities (1) | $ | 8,994,988 |  | $ | 9,423,406 |
(1)Accrued interest receivable totaled $36.4 million and $42.0 million at March 31, 2026 and December 31, 2025, respectively, and was included within other assets on the consolidated balance sheets.
Summary Of Available For Sale Investment Securities By Maturity Groupings | A summary of the available for sale debt securities by maturity groupings as of March 31, 2026 is shown below. The investment portfolio includes agency mortgage-backed securities, which are guaranteed by agencies such as FHLMC, FNMA, and Government National Mortgage Association (GNMA), in addition to non-agency mortgage-backed securities, which have no guarantee but are collateralized by commercial and residential mortgages. Also included are certain other asset-backed securities, which are primarily collateralized by credit cards, automobiles, student loans, and commercial loans. These securities differ from traditional debt securities primarily in that they may have uncertain maturity dates and are priced based on estimated prepayment rates on the underlying collateral.
(In thousands) | Amortized Cost | Fair Value
U.S. government and federal agency obligations: |  |
Within 1 year | $ | 422,299 |  | $ | 423,185 |
After 1 but within 5 years | 1,704,983 |  | 1,707,211 |
After 5 but within 10 years | 913,297 |  | 910,616 |
After 10 years | 106,606 |  | 106,281 |
Total U.S. government and federal agency obligations | 3,147,185 |  | 3,147,293 |
Government-sponsored enterprise obligations: |  |
After 1 but within 5 years | 3,962 |  | 3,737 |
After 5 but within 10 years | 30,816 |  | 26,321 |
After 10 years | 19,821 |  | 13,927 |
Total government-sponsored enterprise obligations | 54,599 |  | 43,985 |
State and municipal obligations: |  |
Within 1 year | 55,782 |  | 55,348 |
After 1 but within 5 years | 428,431 |  | 409,208 |
After 5 but within 10 years | 116,777 |  | 103,102 |
After 10 years | 104,874 |  | 87,166 |
Total state and municipal obligations | 705,864 |  | 654,824 |
Mortgage and asset-backed securities: |  |
Agency mortgage-backed securities | 3,701,146 |  | 3,123,669 |
Non-agency mortgage-backed securities | 446,168 |  | 414,777 |
Asset-backed securities | 1,104,943 |  | 1,093,819 |
Total mortgage and asset-backed securities | 5,252,257 |  | 4,632,265 |
Other debt securities: |  |
Within 1 year | 8,021 |  | 7,924 |
After 1 but within 5 years | 59,891 |  | 55,915 |
After 5 but within 10 years | 81,872 |  | 80,151 |
After 10 years | 23,937 |  | 23,770 |
Total other debt securities | 173,721 |  | 167,760 |
Total available for sale debt securities | $ | 9,333,626 |  | $ | 8,646,127 |
Securities With Unrealized Losses and Length of Impairment Period | The table below summarizes debt securities available for sale in an unrealized loss position, aggregated by length of loss period, for which an allowance for credit losses has not been recorded at March 31, 2026 and December 31, 2025. Unrealized losses on these available for sale securities have not been recognized into income because after review, the securities were deemed not to be impaired. The unrealized losses on these securities are primarily attributable to changes in interest rates and current market conditions. At March 31, 2026, the Company does not intend to sell the securities, nor is it anticipated that it would be required to sell any of these securities at a loss.
| Less than 12 months |  | 12 months or longer |  | Total
(In thousands) | Fair Value | Unrealized Losses |  | Fair Value | Unrealized Losses |  | Fair Value | Unrealized Losses
March 31, 2026 |  |  |  |  |  |  |  |
U.S. government and federal agency obligations | $ | 1,321,452 |  | $ | 9,277 |  |  | $ | 190,275 |  | $ | 7,123 |  |  | $ | 1,511,727 |  | $ | 16,400 |
Government-sponsored enterprise obligations | — |  | — |  |  | 43,985 |  | 10,614 |  |  | 43,985 |  | 10,614 |
State and municipal obligations | 30,515 |  | 118 |  |  | 614,192 |  | 50,935 |  |  | 644,707 |  | 51,053 |
Mortgage and asset-backed securities: |  |  |  |  |  |  |  |
Agency mortgage-backed securities | 3,670 |  | 47 |  |  | 3,047,265 |  | 578,793 |  |  | 3,050,935 |  | 578,840 |
Non-agency mortgage-backed securities | — |  | — |  |  | 401,037 |  | 31,665 |  |  | 401,037 |  | 31,665 |
Asset-backed securities | 68,558 |  | 181 |  |  | 514,421 |  | 16,102 |  |  | 582,979 |  | 16,283 |
Total mortgage and asset-backed securities | 72,228 |  | 228 |  |  | 3,962,723 |  | 626,560 |  |  | 4,034,951 |  | 626,788 |
Other debt securities | 18,832 |  | 10 |  |  | 93,283 |  | 6,578 |  |  | 112,115 |  | 6,588 |
Total | $ | 1,443,027 |  | $ | 9,633 |  |  | $ | 4,904,458 |  | $ | 701,810 |  |  | $ | 6,347,485 |  | $ | 711,443 |
December 31, 2025 |  |  |  |  |  |  |  |
U.S. government and federal agency obligations | $ | 612,167 |  | $ | 2,620 |  |  | $ | 314,006 |  | $ | 8,244 |  |  | $ | 926,173 |  | $ | 10,864 |
Government-sponsored enterprise obligations | — |  | — |  |  | 44,712 |  | 10,239 |  |  | 44,712 |  | 10,239 |
State and municipal obligations | 12,157 |  | 18 |  |  | 636,492 |  | 50,323 |  |  | 648,649 |  | 50,341 |
Mortgage and asset-backed securities: |  |  |  |  |  |  |  |
Agency mortgage-backed securities | 2,437 |  | 30 |  |  | 3,148,627 |  | 565,056 |  |  | 3,151,064 |  | 565,086 |
Non-agency mortgage-backed securities | — |  | — |  |  | 421,508 |  | 31,942 |  |  | 421,508 |  | 31,942 |
Asset-backed securities | 32,875 |  | 36 |  |  | 546,984 |  | 16,925 |  |  | 579,859 |  | 16,961 |
Total mortgage and asset-backed securities | 35,312 |  | 66 |  |  | 4,117,119 |  | 613,923 |  |  | 4,152,431 |  | 613,989 |
Other debt securities | — |  | — |  |  | 110,038 |  | 6,661 |  |  | 110,038 |  | 6,661 |
Total | $ | 659,636 |  | $ | 2,704 |  |  | $ | 5,222,367 |  | $ | 689,390 |  |  | $ | 5,882,003 |  | $ | 692,094 |
Available For Sale Securities Unrealized Gains And Losses By Security Type | For debt securities classified as available for sale, the following table shows the amortized cost, fair value, and allowance for credit losses of securities available for sale at March 31, 2026 and December 31, 2025, and the corresponding amounts of gross unrealized gains and losses (pre-tax) in AOCI, by security type.
(In thousands) | Amortized Cost | Gross Unrealized Gains | Gross Unrealized Losses | Allowance for Credit Losses | Fair Value
March 31, 2026 |  |  |  |  |
U.S. government and federal agency obligations | $ | 3,147,185 |  | $ | 16,508 |  | $ | (16,400) |  | $ | — |  | $ | 3,147,293 |
Government-sponsored enterprise obligations | 54,599 |  | — |  | (10,614) |  | — |  | 43,985 |
State and municipal obligations | 705,864 |  | 13 |  | (51,053) |  | — |  | 654,824 |
Mortgage and asset-backed securities: |  |  |  |  |
Agency mortgage-backed securities | 3,701,146 |  | 1,363 |  | (578,840) |  | — |  | 3,123,669 |
Non-agency mortgage-backed securities | 446,168 |  | 274 |  | (31,665) |  | — |  | 414,777 |
Asset-backed securities | 1,104,943 |  | 5,159 |  | (16,283) |  | — |  | 1,093,819 |
Total mortgage and asset-backed securities | 5,252,257 |  | 6,796 |  | (626,788) |  | — |  | 4,632,265 |
Other debt securities | 173,721 |  | 627 |  | (6,588) |  | — |  | 167,760 |
Total | $ | 9,333,626 |  | $ | 23,944 |  | $ | (711,443) |  | $ | — |  | $ | 8,646,127 |
December 31, 2025 |  |  |  |  |
U.S. government and federal agency obligations | $ | 3,257,561 |  | $ | 32,403 |  | $ | (10,864) |  | $ | — |  | $ | 3,279,100 |
Government-sponsored enterprise obligations | 54,951 |  | — |  | (10,239) |  | — |  | 44,712 |
State and municipal obligations | 715,037 |  | 37 |  | (50,341) |  | — |  | 664,733 |
Mortgage and asset-backed securities: |  |  |  |  |
Agency mortgage-backed securities | 3,786,811 |  | 1,380 |  | (565,086) |  | — |  | 3,223,105 |
Non-agency mortgage-backed securities | 467,200 |  | 430 |  | (31,942) |  | — |  | 435,688 |
Asset-backed securities | 1,269,503 |  | 9,503 |  | (16,961) |  | — |  | 1,262,045 |
Total mortgage and asset-backed securities | 5,523,514 |  | 11,313 |  | (613,989) |  | — |  | 4,920,838 |
Other debt securities | 191,215 |  | 1,576 |  | (6,661) |  | — |  | 186,130 |
Total | $ | 9,742,278 |  | $ | 45,329 |  | $ | (692,094) |  | $ | — |  | $ | 9,095,513 |
Proceeds From Sales Of Securities And Components Of Investment Securities Gains And Losses | The following table presents proceeds from sales of securities and the components of investment securities gains and losses which have been recognized in earnings.
| For the Three Months Ended March 31
(In thousands) | 2026 | 2025
Proceeds from sales of securities: |  |
Other investments | $ | 17,662 |  | $ | 6,757 |
Total proceeds | $ | 17,662 |  | $ | 6,757 |
Investment securities gains (losses), net: |  |
Available for sale debt securities: |  |
Gains realized on sales | $ | — |  | $ | 4 |
Equity securities: |  |
Gains (losses) on equity securities, net | 160 |  | (97) |
Other: |  |
Gains realized on sales | 597 |  | 1,071 |
Losses realized on sales | — |  | (44) |
Fair value adjustments, net | 10,890 |  | (8,525) |
Total investment securities gains (losses), net | $ | 11,647 |  | $ | (7,591) |

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