CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS (Parenthetical) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Comprehensive Income [Abstract]
Unrealized gain on investments and other financial instruments, income tax expense	$ 0.1	$ 0.2	$ 3.1	$ 0.1
Unrealized earnings (losses) of investments in unconsolidated affiliates, income tax expense (benefit)	1.3	(1.2)	(0.4)	0.9
Reclassification adjustments for unrealized gains and losses on investments and other financial instruments, net of tax, (excluding investments in unconsolidated affiliates) included in net earnings, income tax benefit		0.1		0.1
Reclassification adjustments for unrealized earnings and losses of unconsolidated affiliates, tax expense	$ 0.5	$ 1.2	$ 12.3	$ 2.5

Other Comprehensive Income Loss Reclassification Adjustment For Net Unrealized Gains Losses On Unconsolidated Affiliates, Net Of Tax, Include Net Earnings

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- Definition

Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) On Equity Method Investments Arising During Period, Tax

+ References

No definition available.

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- Definition

Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

+ References

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-Publisher FASB
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- Definition

Amount, before adjustment, of tax expense (benefit) for unrealized holding gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Excludes tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

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-Publisher FASB
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (f)
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