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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, 2018	Dec. 31, 2017	Dec. 31, 2016
Shares
Balance	147	147	148
Granted	22	22	24
Vested	(27)	(20)	(25)
Forfeited	(2)	(2)
Amortization of Compensation Expense
Balance	140	147	147
Unearned compensation
Balance	$ 1,785	$ 1,764	$ 1,696
Granted	827	799	750
Vested
Forfeited	(18)	(54)
Amortization of Compensation Expense	(956)	(724)	(682)
Balance	$ 1,638	$ 1,785	$ 1,764
Weighted Average Grant Price
Granted	$ 36.53	$ 36.95	$ 30.85

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