Reinsurance (Schedule of Reinsurance Ceded and Recoveries) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Reinsurance [Abstract]
Ceded earned premiums	$ 76,309	$ 68,635	$ 146,455	$ 130,264
Reinsurance recoveries	$ 58,975	$ 43,989	$ 107,564	$ 93,427

Amount of earned premiums ceded to other entities.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Name:	us-gaap_CededPremiumsEarned
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration