The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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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.

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No definition available.

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Sum of the carrying amounts as of the balance sheet date of all investments.

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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- Definition

The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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- Definition

Provision For Credit Losses Related To Equity Investments

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No definition available.

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Fair Value Measurements - (Details) - USD ($)		3 Months Ended
Fair Value Measurements - (Details) - USD ($)	Feb. 01, 2020	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Consideration transferred		$ 63,800,000	$ 0
Provision for credit losses related to equity investments		0
Equity method investments		14,000,000.0		$ 14,000,000
Limited Partner
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Provision for credit losses related to equity investments		0
Equity method investments		13,800,000		13,100,000
Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Registered investment companies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Registered investment companies		3,000,000.0		$ 3,600,000
Vexcel
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments		$ 129,700,000
Vexcel \| Imagery Sourcing Group
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Consideration transferred	$ 63,800,000
Ownership interest	35.00%