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Investments (Components of Net Realized and Unrealized Gains (Losses)) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Gain (Loss) on Securities [Line Items]
Unrealized Gain (Loss) on Investments recognized in income on equity securities remaining in our portfolio at end of period	$ 16,473	$ 7,936	$ 1,219
Unrealized gains (losses) recognized in income on equity securities that were sold in the respective period	1,408	3	(9,868)
Total unrealized (losses) recognized in income on equity securities	17,881	7,939	(8,649)
Sale of fixed income securities, available-for-sale	502,911	487,087	$ 594,743
Losses on securities for which we have the intent to sell	$ 519	$ 16,266

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Losses on investment securities for which we have the intent to sell

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The unrealized gains (losses) on equity securities sold during the period.

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Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of unrealized gain (loss) on investment.

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