Investments Textuals (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Equity Securities, FV-NI, Unrealized Gain (Loss)	$ (962.7)	$ 355.6
Net Unrealized Gains Losses Recognized from Changes in Fair Value of Equity Securities Held	(956.8)	367.6
Realized Investment Gains Losses From Impairment	$ 0.0	$ 0.0

Net Unrealized Gains Losses Recognized from Changes in Fair Value of Equity Securities Held

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- Definition

The net realized gains or losses on impairments of investments during the period, not 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 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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- Definition

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.

+ References

No definition available.

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