Reinsurance and Catastrophes - Total Amounts of Reinsurance Recoverables On Unpaid Insurance Reserves (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Summary of reinsurance recoverable on unpaid insurance reserves
Reinsurance Recoverables	$ 68,446	$ 70,474
Reinsurance companies
Summary of reinsurance recoverable on unpaid insurance reserves
Reinsurance Recoverables	6,696	10,239
State insurance facilities
Summary of reinsurance recoverable on unpaid insurance reserves
Reinsurance Recoverables	50,713	50,960
Life and health
Summary of reinsurance recoverable on unpaid insurance reserves
Reinsurance Recoverables	$ 11,037	$ 9,275

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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 20
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6480758&loc=d3e6824-158387

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 310
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6485522&loc=d3e21409-158489

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.(a),6)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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