Reinsurance (Schedule of reconciliation of direct to net premiums on both a written and an earned basis) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Premiums Written
Direct premium	$ 88,580	$ 83,671	$ 127,854	$ 120,051
Assumed premium	3,249	3,396	4,532	4,591
Ceded premium	(6,559)	(8,953)	(8,878)	(11,431)
Net premiums	85,270	78,114	123,508	113,211
Premiums Earned
Direct premium	53,987	48,564	91,179	82,680
Assumed premium	3,249	3,368	4,488	4,539
Ceded premium	(6,559)	(6,279)	(8,878)	(8,757)
Net premiums	$ 50,677	$ 45,653	$ 86,789	$ 78,462
Percentage of assumed premium to net earned premium	6.40%	7.40%	5.20%	5.80%

Amount of written premiums ceded to other entities, includes both credits and debits.

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

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Percentage of assumed premium earned to premium earned after effects of reinsurance, as disclosed in supplementary reinsurance information.

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