Concentration of Risks - By Reinsurer (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
[ReinsuranceRecoverables]	$ 9,530,283	$ 8,520,232
Renaissance Reinsurance U.S., Inc.
[ReinsuranceRecoverables]	4,911,922	4,464,980
Hannover Rusk SE
[ReinsuranceRecoverables]	4,142,308	3,384,341
TOA Re
[ReinsuranceRecoverables]	476,101	670,337
Other
[ReinsuranceRecoverables]	$ (48)	$ 574

Amount, after valuation allowance, recoverable under reinsurance contracts including premium paid under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves.

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.(a),6)
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 20
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=99397103&loc=d3e6824-158387

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 310
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=99404803&loc=d3e21409-158489

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