Investments - Other Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Schedule of Investments [Line Items]
Fair value	$ 42,026	$ 4,877
% of Total fair value	100.00%	100.00%
Other investments	$ 75,364	$ 31,748
Hedge fund investments
Schedule of Investments [Line Items]
Fair value	$ 25,376	$ 0
% of Total fair value	60.40%	0.00%
Investment in limited partnerships
Schedule of Investments [Line Items]
Fair value	$ 13,850	$ 3,077
% of Total fair value	33.00%	63.10%
Unfunded commitment on investments in limited partnerships	$ 333	$ 340
Other
Schedule of Investments [Line Items]
Fair value	$ 2,800	$ 1,800
% of Total fair value	6.60%	36.90%
Investment in special purpose vehicles focused on lending activities
Schedule of Investments [Line Items]
Other investments	$ 33,338	$ 26,871
Unfunded commitment on investments in limited partnerships	$ 23,127	$ 767

Other Investments, Percent of Total Fair Value

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The amount of unfunded commitments for which the entity is obligated, to those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 6A
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=SL6742756-110258

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- Definition

Value of the other investment not readily marketable determined by management based upon fair value methods, including pricing of similar securities and valuation techniques, that was used to record the investment for financial reporting purposes.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 820
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=35710923&loc=d3e45360-110995

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- Definition

Amount of investments classified as other.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(f,g))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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+ References

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