Amount before accretion (amortization) of purchase discount (premium) of interest income and dividend income on nonoperating securities.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(a),(b))
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Amount of expenses related to the managing member or general partner for management of the day-to-day business functions of the limited liability company (LLC) or limited partnership (LP).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
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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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Basis of Financial Statements - Related Party Transactions (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Management fee expenses			$ 15.1
Related Party Transaction [Line Items]
Interest, investment and other income	$ 4.7	$ 1.3	15.2	$ 13.7
Management Services Agreement, fees earned
Related Party Transaction [Line Items]
Interest, investment and other income			$ 9.1