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Fair Value Measurements (Summary Of Gains And Losses On Level 3 Assets And Liabilities) (Details) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2026 | Mar. 31, 2025
Gains and Losses included in earnings for Level 3 assets & liabilities [Line Items] |  |
Change in unrealized gains or losses relating to assets still held at period end | $ 10,890 | $ (8,525)
Investment Securities Gains (Losses), Net |  |
Gains and Losses included in earnings for Level 3 assets & liabilities [Line Items] |  |
Total gains or losses included in earnings | 10,890 | (8,525)
Change in unrealized gains or losses relating to assets still held at period end | $ 10,890 | $ (8,525)

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