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Debt Securities (Amortized Cost, Unrealized Gains And Losses, And Fair Value Of Investment Securities) (Details) - USD ($) $ in Thousands | Jun. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Debt and Equity Securities, FV-NI [Line Items] |  |
Available-for-sale securities, amortized cost | $ 9,071,360 | $ 8,858,329
Available-for-sale securities, unrealized gains | 41,652 | 7,808
Available-for-sale securities, unrealized losses | (459,840) | (591,522)
Available for sale, at fair value | 8,653,172 | 8,274,615
Investment securities held to maturity | 2,013 | 2,101
Held-to-maturity securities, unrealized gains | 572 | 602
Held-to-maturity securities, unrealized losses | 0 | 0
Held-to-maturity securities, fair value | 2,585 | 2,703
U.S. Treasury and agencies |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Available-for-sale securities, amortized cost | 1,391,854 | 1,495,542
Available-for-sale securities, unrealized gains | 5,528 | 1,092
Available-for-sale securities, unrealized losses | (50,322) | (73,847)
Available for sale, at fair value | 1,347,060 | 1,422,787
Obligations of states and political subdivisions |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Available-for-sale securities, amortized cost | 1,041,810 | 1,055,535
Available-for-sale securities, unrealized gains | 3,275 | 2,779
Available-for-sale securities, unrealized losses | (30,202) | (32,261)
Available for sale, at fair value | 1,014,883 | 1,026,053
Mortgage-backed securities and collateralized mortgage obligations |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Available-for-sale securities, amortized cost | 6,637,696 | 6,307,252
Available-for-sale securities, unrealized gains | 32,849 | 3,937
Available-for-sale securities, unrealized losses | (379,316) | (485,414)
Available for sale, at fair value | 6,291,229 | 5,825,775
Investment securities held to maturity | 2,013 | 2,101
Held-to-maturity securities, unrealized gains | 572 | 602
Held-to-maturity securities, unrealized losses | 0 | 0
Held-to-maturity securities, fair value | $ 2,585 | $ 2,703

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- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-2 + Details
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