Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 6,920	$ 5,674	$ 11,093	$ 10,140
Other comprehensive income, before tax:
Amortization of unrecognized loss	0	2	0	4
Unrealized (losses) gains on investments arising during the period	(258)	1,396	(1,918)	3,062
Reclassification adjustment for sales of securities included in net income	0	(83)	0	(173)
Other comprehensive (loss) income, before tax	(258)	1,315	(1,918)	2,893
Income tax expense related to postretirement health benefits	0	0	0	1
Income tax (benefit) expense related to unrealized (losses) gains on investments arising during the period	(55)	476	(406)	1,045
Income tax benefit related to reclassification adjustment for sales of securities included in net income	0	(28)	0	(60)
Net income tax (benefit) expense on other comprehensive (loss) income	(55)	448	(406)	986
Other comprehensive (loss) income	(203)	867	(1,512)	1,907
Comprehensive Income	6,717	6,541	9,581	12,047
Comprehensive loss attributable to noncontrolling interests	27	1	30	11
Comprehensive Income Attributable to the Company	$ 6,744	$ 6,542	$ 9,611	$ 12,058