Employee Benefit Plans (Components of Postretirement Benefit Expense) (Details) - Postretirement Medical and Life Benefit Plan - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Service Cost	$ 119	$ 110	$ 83
Interest Cost	28	41	43
Amortization of Prior Service Costs	(2)	2	0
Amortization of Unrecognized Net (Gain) Loss	55	64	37
Net Postretirement Benefit Expense	200	217	163
Net Gain (Loss) During Period Recognized in Other Comprehensive Income (Loss)	(121)	15	273
Total Recognized in Net Postretirement Benefit Expense and Other Comprehensive Income	$ 79	$ 232	$ 436