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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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- Definition

Represents the unrealized holding gain or loss included in the fair value of trading securities as of the balance sheet date.

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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