Reinsurance (Schedule of Reinsurance Ceded and Recoveries) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Reinsurance [Abstract]
Ceded earned premiums	$ 83,242	$ 73,038	$ 229,697	$ 203,302
Reinsurance recoveries	$ 50,564	$ 48,962	$ 158,128	$ 142,389

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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Name:	us-gaap_CededPremiumsEarned
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration