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Employee Benefit Plans (Schedule of Restricted Stock Plan) (Details) - 2008 Restricted Stock Plan [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Shares
Balance	86	97	125
Granted	15	16	18
Vested	(18)	(27)	(28)
Forfeited			(18)
Amortization of Compensation Expense
Balance	83	86	97
Unearned compensation
Balance	$ 1,837	$ 1,706	$ 1,638
Granted	1,151	982	975
Vested
Forfeited
Amortization of Compensation Expense	(1,057)	(851)	(907)
Balance	$ 1,931	$ 1,837	$ 1,706
Weighted Average Grant Price
Granted	$ 79.02	$ 60.12	$ 55.99

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