Schedule IV (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Abstract]
Direct Premiums Written	$ 1,148,190	$ 989,525	$ 708,252
Ceded Premiums Written	512,270	447,329	262,340
Assumed Premiums Written	104,211	51,323	(96)
Premiums Written, Net	$ 740,131	$ 593,519	$ 445,816
premiums assumed as percentage of net premiums	14.10%	8.60%	0.00%

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premiums assumed as percentage of net premiums

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Amount of written premiums assumed from other entities.

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-Publisher FASB
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Amount of written premiums ceded to other entities.

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Amount, before premiums ceded to other entities and premiums assumed by the entity, of premiums written.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums written.

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-Publisher FASB
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