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Trading Securities (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Schedule of Trading Securities [Line Items] |  |
Trading Securities, Fair Value | $ 4,255,732 | $ 4,899,090
Trading Securities, Net Unrealized Gain (Loss) | 20,108 | (38,032)
U.S. government securities [Member] |  |
Schedule of Trading Securities [Line Items] |  |
Trading Securities, Fair Value | 4,821 | 21,275
Trading Securities, Net Unrealized Gain (Loss) | 9 | (60)
Residential agency mortgage-backed securities [Member] |  |
Schedule of Trading Securities [Line Items] |  |
Trading Securities, Fair Value | 4,133,011 | 4,792,695
Trading Securities, Net Unrealized Gain (Loss) | 20,064 | (37,439)
Municipal securities [Member] |  |
Schedule of Trading Securities [Line Items] |  |
Trading Securities, Fair Value | 74,613 | 62,230
Trading Securities, Net Unrealized Gain (Loss) | (55) | (566)
Other trading securities [Member] |  |
Schedule of Trading Securities [Line Items] |  |
Trading Securities, Fair Value | 43,287 | 22,890
Trading Securities, Net Unrealized Gain (Loss) | $ 90 | $ 33

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