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Investments (Unrealized Gains on Investments) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Net unrealized (losses) gains	$ (527,891)	$ 228,963	$ 386,393
Deferred income tax	110,857	(48,082)	(81,142)
Net unrealized (losses) gains, net of deferred income tax	(417,034)	180,881	305,251
(Decrease) Increase in net unrealized gains in OCI, net of deferred income tax	(597,915)	(124,370)	(134,857)
Available-for-sale Securities [Member]
Net unrealized (losses) gains	(527,926)	228,947	386,380
Total HTM Securities [Member]
Net unrealized (losses) gains	0	(4)	7
Short-term Investments [Member]
Net unrealized (losses) gains	$ 35	$ 20	$ 6

X

- Definition

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

+ References

No definition available.

+ Details

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X

- 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

Total change in unrealized gains/losses on investment securities net of tax.

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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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- Details

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