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Investments - Schedule of Unrealized Gains (Losses) on Investments (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Gain (Loss) on Securities [Line Items] |  |  |
Total net unrealized gains (losses) | $ (316,788) | $ (353,253) | $ (527,891)
Deferred income tax | 66,526 | 74,184 | 110,857
Net unrealized gains (losses), net of deferred income tax | (250,262) | (279,069) | (417,034)
Increase (decrease) in net unrealized gains (losses) in OCI, net of deferred income tax | 28,807 | 137,965 | (597,915)
AFS securities |  |  |
Gain (Loss) on Securities [Line Items] |  |  |
Total net unrealized gains (losses) | (316,796) | (353,288) | (527,926)
Short-term securities |  |  |
Gain (Loss) on Securities [Line Items] |  |  |
Total net unrealized gains (losses) | $ 8 | $ 35 | $ 35

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- Definition Amount, after tax and adjustment, of unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) and unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(19)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 10A -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-10A Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 10A -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-10A Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 11 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-11 + Details
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