Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Statement of Comprehensive Income [Abstract]
Net income	$ 6,185	$ 13,823
Other comprehensive income, before tax:
Accumulated postretirement benefit obligation adjustment	219	0
Net unrealized losses on investments arising during the period	(2,764)	(750)
Reclassification adjustment for sale of securities included in net income	0	(23)
Other comprehensive loss, before tax	(2,545)	(773)
Income tax expense related to postretirement health benefits	46	0
Income tax benefit related to net unrealized losses on investments arising during the period	(583)	(158)
Income tax benefit related to reclassification adjustment for sale of securities included in net income	0	(5)
Net income tax benefit on other comprehensive loss	(537)	(163)
Other comprehensive loss	(2,008)	(610)
Comprehensive Income	$ 4,177	$ 13,213