Reinsurance And Policy Benefits And Losses Claims And Loss Expenses Payable (Cumulative Paid Claims And Allocated Claim Adjustment Expense Net Of Reinsurance) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Incurred claims development [Abstract]
Shortduration Insurance Contracts Cumulative Paid Claims And Allocated Claim Adjustment Expense Net	$ 56,968
All outstanding liabilities before 2012, net of reinsurance	125,740
Liabilities for claims and claim adjustment expenses, net of reinsurance	139,064
Accident Year 2012 [Member] | Property and Casualty Insurance [Member]
Incurred claims development [Abstract]
Shortduration Insurance Contracts Cumulative Paid Claims And Allocated Claim Adjustment Expense Net	8,735	$ 8,734	$ 8,410	$ 8,179	$ 6,345	$ 4,415
Accident Year 2013 [Member] | Property and Casualty Insurance [Member]
Incurred claims development [Abstract]
Shortduration Insurance Contracts Cumulative Paid Claims And Allocated Claim Adjustment Expense Net	9,576	9,462	8,718	7,608	$ 5,227
Accident Year 2014 [Member] | Property and Casualty Insurance [Member]
Incurred claims development [Abstract]
Shortduration Insurance Contracts Cumulative Paid Claims And Allocated Claim Adjustment Expense Net	9,293	9,270	8,087	$ 6,154
Accident Year 2015 [Member] | Property and Casualty Insurance [Member]
Incurred claims development [Abstract]
Shortduration Insurance Contracts Cumulative Paid Claims And Allocated Claim Adjustment Expense Net	9,730	9,601	$ 7,509
Accident Year 2016 [Member] | Property and Casualty Insurance [Member]
Incurred claims development [Abstract]
Shortduration Insurance Contracts Cumulative Paid Claims And Allocated Claim Adjustment Expense Net	10,665	$ 7,777
Accident Year 2017 [Member] | Property and Casualty Insurance [Member]
Incurred claims development [Abstract]
Shortduration Insurance Contracts Cumulative Paid Claims And Allocated Claim Adjustment Expense Net	$ 8,970