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Reinsurance - Summary of Quota Reinsurance Arrangements (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017
Effects of Reinsurance [Line Items]
Ceded losses incurred	$ 2,736	$ (508)	$ 7,841	$ 3,810
Reinsurance recoverable on loss reserves	19,566	33,281	19,566	33,281	$ 33,328	$ 48,474
Quota Share Reinsurance Agreements, Excluding Captive Agreements
Effects of Reinsurance [Line Items]
Ceded premiums written and earned, net of profit commission	23,032	25,248	87,721	79,716
Ceded losses incurred	2,729	(522)	7,845	3,531
Ceding commissions	11,042	12,983	37,807	38,268
Profit commission	32,177	$ 39,664	108,079	$ 111,622
Reinsurance recoverable on loss reserves	$ 19,500		$ 19,500		$ 33,200

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- Definition

Ceded Premiums Written and Earned, Net of Profit Commission

+ References

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- Definition

Reinsurance Ceding Commission Earned

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Reinsurance, Profit Commission

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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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No definition available.

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- Definition

Amount of reduction of provision for policy benefits and costs incurred for policies ceded.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=99397103&loc=d3e6811-158387

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- Definition

Amount, after valuation allowance, recoverable under reinsurance contracts for losses reported to the ceding insurer but not yet paid and amounts expected for incurred losses and settlement expenses, which have not yet been reported to the ceding insurer.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 310
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=99404803&loc=d3e21412-158489

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
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-URI http://asc.fasb.org/extlink&oid=99397103&loc=d3e6824-158387

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 50
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-URI http://asc.fasb.org/extlink&oid=116884095&loc=d3e14764-158437

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-URI http://asc.fasb.org/extlink&oid=116884095&loc=d3e14764-158437

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