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Recent Developments Related to COVID-19 Income Statement (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Statement [Abstract]
Net investment gains (losses)	$ 911,243	$ 425,653	$ (770,198)	$ 1,037,844
Change in fair value of equity securities	$ 914,055	$ 425,720	$ (777,124)	$ 1,037,230

X

- Definition

The net gains or losses on investments during the period, also including gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=116654751&loc=SL75117546-209714

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- References

No definition available.

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