Real Estate Fund Investments - Schedule of Income from Unconsolidated Real Estate Funds Investment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Real Estate Fund Disclosure [Abstract]
Investment income	$ 29,013	$ 20,484
Investment expenses	7,086	7,466
Net investment income	21,927	13,018
Net realized losses	(72,134)
Previously recorded unrealized losses	35,682
Net unrealized (losses) gains	(6,266)	14,275
(Loss) income from real estate fund investments	$ (20,791)	$ 27,293

Equity method investment summarized financial information income (loss) from real estate fund investments.

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Equity method investment summarized financial information investment expenses.

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Equity method investment summarized financial information investment income.

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Equity method investment summarized financial information investment income (loss) net.

No definition available.

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Equity method investment summarized financial information previously recorded unrealized gain (losses) net.

No definition available.

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Equity method investment summarized financial information realized gain (losses) net.

No definition available.

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Equity method investment summarized financial information unrealized gain (losses) net.

No definition available.

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Real estate fund disclosure.

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