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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
	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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