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Derivative Instruments (Schedule Of Notional Amounts Of Derivative Instruments) (Details) - USD ($) $ in Thousands | Mar. 31, 2026 | Dec. 31, 2025
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Derivative [Line Items] |  |
Derivative, Notional Amount | $ 5,182,136 | $ 4,593,942
Interest rate swaps |  |
Derivative [Line Items] |  |
Derivative, Notional Amount | 2,063,942 | 1,968,679
Interest Rate Floor |  |
Derivative [Line Items] |  |
Derivative, Notional Amount | 2,500,000 | 2,000,000
Interest rate caps |  |
Derivative [Line Items] |  |
Derivative, Notional Amount | 120,000 | 105,770
Credit risk participation agreements |  |
Derivative [Line Items] |  |
Derivative, Notional Amount | 473,785 | 474,951
Foreign exchange contracts |  |
Derivative [Line Items] |  |
Derivative, Notional Amount | 14,817 | 29,451
Mortgage loan commitments |  |
Derivative [Line Items] |  |
Derivative, Notional Amount | 5,252 | 6,297
Mortgage loan forward sale contracts |  |
Derivative [Line Items] |  |
Derivative, Notional Amount | 840 | 1,794
Forward TBA contracts |  |
Derivative [Line Items] |  |
Derivative, Notional Amount | $ 3,500 | $ 7,000

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