Income Taxes (Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Deferred tax assets:
20% of net unearned premiums	$ 52,644	$ 47,110
Discounting of loss reserves and salvage and subrogation recoverable for tax purposes	9,245	6,451
Write-down of impaired investments	356	387
Tax credit carryforwards	0	230
Expense accruals	7,019	6,192
Tax asset on net unrealized loss on securities carried at fair value	1,055	0
Other deferred tax assets	3,257	3,174
Total gross deferred tax assets	73,576	63,544
Deferred tax liabilities:
Deferred policy acquisition costs	(45,178)	(41,612)
Tax liability on net unrealized gain on securities carried at fair value	0	(27,574)
Tax depreciation in excess of book depreciation	(4,594)	(5,686)
Undistributed earnings of insurance subsidiaries	(3,017)	(3,907)
Tax amortization in excess of book amortization	(2,729)	(2,280)
Other deferred tax liabilities	(4,719)	(5,417)
Total gross deferred tax liabilities	(60,237)	(86,476)
Net deferred tax assets	$ 13,339
Net deferred tax liabilities		$ (22,932)