Reinsurance and Policy Benefits and Losses, Claims, and Loss Expenses Payable (Incurred Claims Development) (Details) $ in Thousands	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Incurred claims development [Abstract]
Shortduration Insurance Contracts Incurred But Not Reported Ibnr Claims Liability Net	$ 16,285
Shortduration Insurance Contracts Number Of Reported Claims	11,199
Accident Year 2014 [Member]
Incurred claims development [Abstract]
Shortduration Insurance Contracts Incurred Claims And Allocated Claim Adjustment Expense Net	$ 10,327	$ 10,493	$ 10,748	$ 10,759	$ 10,720	$ 10,907	$ 11,691
Shortduration Insurance Contracts Incurred But Not Reported Ibnr Claims Liability Net	$ 0
Shortduration Insurance Contracts Number Of Reported Claims	10,068
Accident Year 2015 [Member]
Incurred claims development [Abstract]
Shortduration Insurance Contracts Incurred Claims And Allocated Claim Adjustment Expense Net	$ 11,092	11,087	12,464	12,460	12,459	$ 12,214
Shortduration Insurance Contracts Incurred But Not Reported Ibnr Claims Liability Net	$ 0
Shortduration Insurance Contracts Number Of Reported Claims	11,104
Accident Year 2016 [Member]
Incurred claims development [Abstract]
Shortduration Insurance Contracts Incurred Claims And Allocated Claim Adjustment Expense Net	$ 11,764	11,790	13,056	13,011	$ 13,297
Shortduration Insurance Contracts Incurred But Not Reported Ibnr Claims Liability Net	$ 0
Shortduration Insurance Contracts Number Of Reported Claims	11,469
Accident Year 2017 [Member]
Incurred claims development [Abstract]
Shortduration Insurance Contracts Incurred Claims And Allocated Claim Adjustment Expense Net	$ 15,538	17,078	16,109	$ 15,748
Shortduration Insurance Contracts Incurred But Not Reported Ibnr Claims Liability Net	$ 305
Shortduration Insurance Contracts Number Of Reported Claims	12,100
Accident Year 2018 [Member]
Incurred claims development [Abstract]
Shortduration Insurance Contracts Incurred Claims And Allocated Claim Adjustment Expense Net	$ 18,027	18,386	$ 19,580
Shortduration Insurance Contracts Incurred But Not Reported Ibnr Claims Liability Net	$ 1,464
Shortduration Insurance Contracts Number Of Reported Claims	11,981
Accident Year 2019 [Member]
Incurred claims development [Abstract]
Shortduration Insurance Contracts Incurred Claims And Allocated Claim Adjustment Expense Net	$ 26,316	$ 22,138
Shortduration Insurance Contracts Incurred But Not Reported Ibnr Claims Liability Net	$ 4,379
Shortduration Insurance Contracts Number Of Reported Claims	11,738
Accident Year 2020 [Member]
Incurred claims development [Abstract]
Shortduration Insurance Contracts Incurred Claims And Allocated Claim Adjustment Expense Net	$ 20,671