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Investments (Unrealized Gains (Losses) on Equity Securities) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Gain (Loss) on Securities [Line Items]
Unrealized gains (losses) recognized in income on equity securities on securities remaining in our portfolio at period end.	$ (2,220)	$ 10,097
Unrealized (losses) gains recognized in income on equity securities on securities sold during period	66	1,183
Total unrealized (losses) gains recognized in income on equity securities	(2,154)	$ 11,280
Change in Gain (Loss) on Investments	$ (45,500)

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Increase (decrease) in gain (loss) on investments

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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
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-Topic 321
-SubTopic 10
-Section 50
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of unrealized gain (loss) on investment.

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