Investment Funds (Schedule of Investment Funds) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Schedule of Equity Method Investments [Line Items]
Maximum loss exposure	$ 232,000
Investment funds	1,213,535	$ 1,332,818
Income (Losses)	69,194	109,349	$ 68,169
Real estate
Schedule of Equity Method Investments [Line Items]
Investment funds	412,275	642,137
Income (Losses)	19,154	61,453	45,068
Financial services
Schedule of Equity Method Investments [Line Items]
Investment funds	280,705	195,706
Income (Losses)	29,005	11,044	3,762
Energy
Schedule of Equity Method Investments [Line Items]
Investment funds	156,869	183,627
Income (Losses)	(18,136)	7,084	6,147
Transportation
Schedule of Equity Method Investments [Line Items]
Investment funds	147,034	136,640
Income (Losses)	14,193	15,390	1,686
Other funds
Schedule of Equity Method Investments [Line Items]
Investment funds	216,652	174,708
Income (Losses)	$ 24,978	$ 14,378	$ 11,506

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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