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Investments (Unrealized Gains on Investments) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Net unrealized (losses) gains	$ (353,253)	$ (527,891)	$ 228,963
Deferred income tax	74,184	110,857	(48,082)
Net unrealized (losses) gains, net of deferred income tax	(279,069)	(417,034)	180,881
Increase (decrease) in net unrealized gains (losses) in OCI, net of deferred income tax	137,965	(597,915)	(124,370)
Available-for-sale Securities [Member]
Net unrealized (losses) gains	(353,288)	(527,926)	228,947
Total HTM Securities [Member]
Net unrealized (losses) gains	0	0	(4)
Short-term Investments [Member]
Net unrealized (losses) gains	$ 35	$ 35	$ 20

X

- Definition

Tax effect of unrealized gain (loss) on investments in accumulated other comprehensive income.

+ References

No definition available.

+ Details

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- Definition

This item represents the net unrealized gains (losses) on investments in other comprehensive income, net of deferred income tax.

+ References

No definition available.

+ Details

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- Definition

This item represents the net unrealized gains (losses) on investments in other comprehensive income.

+ References

No definition available.

+ Details

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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 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 2: 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 3: 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

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