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v3.23.1

Investment Securities (Amortized Cost, Unrealized Gains And Losses, And Fair Value Of Investment Securities) (Details) - USD ($) $ in Thousands | Mar. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Investment Holdings [Line Items] |  |
Available-for-sale securities, amortized cost | $ 9,646,277 | $ 3,738,281
Available-for-sale securities, unrealized gains | 94,099 | 234
Available-for-sale securities, unrealized losses | (490,776) | (542,349)
Available for sale, at fair value | 9,249,600 | 3,196,166
Investment securities held to maturity | 2,432 | 2,476
Held-to-maturity securities, unrealized gains | 743 | 721
Held-to-maturity securities, unrealized losses | 0 | 0
Held-to-maturity securities, fair value | 3,175 | 3,197
U.S. Treasury and agencies |  |
Investment Holdings [Line Items] |  |
Available-for-sale securities, amortized cost | 1,584,480 | 1,035,532
Available-for-sale securities, unrealized gains | 3,940 | 0
Available-for-sale securities, unrealized losses | (86,058) | (99,358)
Available for sale, at fair value | 1,502,362 | 936,174
Obligations of states and political subdivisions |  |
Investment Holdings [Line Items] |  |
Available-for-sale securities, amortized cost | 1,086,982 | 297,610
Available-for-sale securities, unrealized gains | 21,327 | 231
Available-for-sale securities, unrealized losses | (22,124) | (28,041)
Available for sale, at fair value | 1,086,185 | 269,800
Mortgage-backed securities and collateralized mortgage obligations |  |
Investment Holdings [Line Items] |  |
Available-for-sale securities, amortized cost | 6,974,815 | 2,405,139
Available-for-sale securities, unrealized gains | 68,832 | 3
Available-for-sale securities, unrealized losses | (382,594) | (414,950)
Available for sale, at fair value | 6,661,053 | 1,990,192
Investment securities held to maturity | 2,432 | 2,476
Held-to-maturity securities, unrealized gains | 743 | 721
Held-to-maturity securities, unrealized losses | 0 | 0
Held-to-maturity securities, fair value | $ 3,175 | $ 3,197

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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563 + Details
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- Definition Amount, before tax, of unrealized loss 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563 + Details
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- Definition Amortized cost of 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 -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454 + Details
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