Property and Casualty Unpaid Claims and Claim Expenses - Reconciliation of Net Incurred and Paid Claims (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Liability for Claims and Claims Adjustment Expense, Total	$ 396,714	$ 347,749
Property, Liability and Casualty Insurance Product Line [Member]
Reinsurance Recoverables, Including Reinsurance Premium Paid	89,725
Short-duration Insurance Contracts, Liability for Unpaid Claims and Claims Adjustment Expense, Accumulated Unallocated Claim Adjustment Expense	22,483
Liability For Other Than Short Duration And Unallocated Claims Adjustment Expenses	52,017
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net	254,972
Property, Liability and Casualty Insurance Product Line [Member] | Homeowners
Reinsurance Recoverables, Including Reinsurance Premium Paid	26,646
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net	41,039
Property, Liability and Casualty Insurance Product Line [Member] | Auto liability
Reinsurance Recoverables, Including Reinsurance Premium Paid	55,971
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net	204,240
Property, Liability and Casualty Insurance Product Line [Member] | Auto physical damage
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net	6,137
Property, Liability and Casualty Insurance Product Line [Member] | Other Short Duration Lines [Member]
Reinsurance Recoverables, Including Reinsurance Premium Paid	7,108
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net	3,556
Property, Liability and Casualty Insurance Product Line [Member] | Other Than Short Duration Line [Member]
Prior years paid	$ 29,534