Investments - Net Gains (Losses) on Trading Securities (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Debt Securities, Trading, Gain (Loss) [Abstract]
Net gains (losses) on trading securities held at period end	$ (2,021)	$ 2,332	$ (5,697)	$ 9,253
Net gains (losses) on trading securities that matured/sold during the period	0	0	0	0
Debt Securities, Trading, Gain (Loss), Total	$ (2,021)	$ 2,332	$ (5,697)	$ 9,253

Amount of unrealized and realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-14

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(7)(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-14

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

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-SubTopic 10
-Topic 825
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482881/825-10-55-10

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-14

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-9

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