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Reinsurance - Amounts Ceded Related to QSR Transactions (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Ceded Credit Risk [Line Items]
Ceded premiums written	$ (9,604)	$ (6,234)	$ (19,411)	$ (13,231)
Ceded premiums earned	(11,931)	(8,994)	(24,360)	(17,683)
Third-Party Reinsurers
Ceded Credit Risk [Line Items]
Ceded risk-in-force	4,558,862	3,606,928	4,558,862	3,606,928
Ceded premiums written	(18,592)	(15,318)	(37,437)	(29,843)
Ceded premiums earned	(20,919)	(18,077)	(42,387)	(34,295)
Ceded claims and claim expenses	770	173	1,669	716
Ceding commission written	3,717	3,064	7,488	5,969
Ceding commission earned	4,171	3,536	8,377	6,687
Profit commission	$ 11,884	$ 10,707	$ 23,945	$ 19,908

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- Definition

Reinsurance Ceded Claims and Claims Expenses

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- Definition

Reinsurance Ceding Commission Earned

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Reinsurance Ceding Commission Written

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Reinsurance Profit Commission

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- Definition

Risk In Force, Ceded

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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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- Definition

Amount of earned premiums ceded to other entities.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 235
-Section S99
-Paragraph 2
-Subparagraph (SX 210.12-17(Column C))
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-Publisher FASB
-Name Accounting Standards Codification
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Amount of written premiums ceded to other entities.

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