Consolidated Statements Of Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Retained Earnings	Accumulated Other Comprehensive Income
Balance, beginning of year, shares at Dec. 31, 2020		1,892
Balance, beginning of year at Dec. 31, 2020	$ 200,422	$ 0	$ 196,096	$ 4,326
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss)	67,020		67,020
Dividends	(37,553)		(37,553)
Exercise of stock appreciation rights (in shares)		3
Exercise of stock appreciation rights	(1)		(1)
Share-based compensation expense related to stock appreciation rights	299		299
Accumulated postretirement benefit obligation adjustment	0
Net unrealized gain (loss) on investments	(1,100)			(1,100)
Balance, end of year, shares at Dec. 31, 2021		1,895
Balance, end of year at Dec. 31, 2021	229,087	$ 0	225,861	3,226
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss)	23,903		23,903
Dividends	(9,181)		(9,181)
Shares of common stock repurchased and retired (in shares)		(1)
Shares of common stock repurchased and retired	(133)		(133)
Exercise of stock appreciation rights (in shares)		3
Exercise of stock appreciation rights	(1)		(1)
Share-based compensation expense related to stock appreciation rights	362		362
Accumulated postretirement benefit obligation adjustment	180			180
Net unrealized gain (loss) on investments	(3,206)			(3,206)
Balance, end of year, shares at Dec. 31, 2022		1,897
Balance, end of year at Dec. 31, 2022	$ 241,011	$ 0	$ 240,811	$ 200