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- Definition

Catastrophe Bond

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- Definition

Equity Method Investment, Counterparty Ownership Percentage

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- Definition

Investment Funds

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Investment Owned, Percentage

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- Definition

Restricted assets.

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No definition available.

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- Definition

This element represents the aggregate cost of investments accounted for under the equity method of accounting.

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- Definition

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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- Definition

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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Amount of investments classified as other.

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The net cash outflow or inflow associated with the acquisition or sale of a business segment during the period.

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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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The cash inflow associated with the sale of 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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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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Investments - Additional Information (Narrative) (Details) - USD ($)			1 Months Ended	12 Months Ended
	Dec. 18, 2017	Jul. 26, 2016	Jan. 31, 2015	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Sep. 19, 2018	Sep. 18, 2018	May 01, 2018	Jan. 01, 2017	Oct. 02, 2012
Gain (Loss) on Securities [Line Items]
Catastrophe bonds, trading, cost				$ 36,200,000	$ 32,400,000
Restricted assets				4,419,200,000	4,638,800,000
Other investments				102,500,000	0
Investment in the period				1,400,000	64,900,000
Proceeds from sale of equity method investments				0	(9,300,000)	$ 0
Equity method investment, aggregate cost				67,100,000	66,400,000	12,100,000
Investment funded				0
Other-than-temporary impairment charge				$ 0	$ 700,000	0
BBB Emerging Market Debt
Gain (Loss) on Securities [Line Items]
Percentage of investment				4.50%
Real estate fund
Gain (Loss) on Securities [Line Items]
Percentage of investment				1.30%
Managed portfolio
Gain (Loss) on Securities [Line Items]
Percentage of investment				5.80%	10.00%
Bene
Gain (Loss) on Securities [Line Items]
Investment in the period		$ 3,300,000		$ 1,200,000	$ 0
Gross realized and unrealized gains (loss)				(900,000)	(300,000)	(100,000)
Proceeds from sale of equity method investments					0
Equity method investment, ownership percentage		20.00%
Equity method investment, aggregate cost				3,200,000	2,900,000	3,200,000
Equity method investment, cash payment				1,200,000
Chaspark
Gain (Loss) on Securities [Line Items]
Investment in the period				0	0
Percentage of ownership acquired											58.50%
Gross realized and unrealized gains (loss)				0	900,000	300,000
Proceeds from sale of equity method investments					(9,300,000)
Equity method investment, aggregate cost				0	0	8,400,000
MVI
Gain (Loss) on Securities [Line Items]
Investment in the period			$ 800,000	200,000	100,000
Gross realized and unrealized gains (loss)				(200,000)	(100,000)	(300,000)
Proceeds from sale of equity method investments					0
Equity method investment, aggregate cost				500,000	500,000	500,000
Digital Re
Gain (Loss) on Securities [Line Items]
Investment in the period				0	2,300,000
Gross realized and unrealized gains (loss)				400,000	0	0
Proceeds from sale of equity method investments					0
Equity method investment, ownership percentage										49.00%
Equity method investment, aggregate cost				900,000	500,000	0				$ 2,300,000
Crop Re
Gain (Loss) on Securities [Line Items]
Investment in the period				0	62,500,000
Proceeds from sale of equity method investments					0
Equity method investment, ownership percentage	23.20%
Equity method investment, aggregate cost	$ 62,500,000			62,500,000	62,500,000	$ 0
Equity method investment, cash payment	$ 5,900,000
AgriLogic Consulting, LLC
Gain (Loss) on Securities [Line Items]
Equity method investment, ownership percentage								40.00%
Equity method investment, aggregate cost								$ 0
CGB Insurance Diversified Services, Inc. \| Crop Re
Gain (Loss) on Securities [Line Items]
Equity method investment, counterparty ownership percentage	76.80%
Limited Partner \| Real estate fund
Gain (Loss) on Securities [Line Items]
Restricted assets				0	100,000,000
Other investments				$ 102,500,000	$ 0		$ 13,800,000		$ 86,200,000
AgriLogic Consulting, LLC \| Consulting Relationships \| Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]
Gain (Loss) on Securities [Line Items]
Sale of interest in consulting business								60.00%