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Employee Benefit Plans (Schedule of Fair Value of Other Benefits Plan Assets) (Details) - Other Benefits Plan [Member] - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Fair value of plan assets	$ 34,622	$ 36,083	$ 31,607
Fair Value, Level 1 [Member]
Fair value of plan assets	21,693	24,322
Fair Value, Level 2 [Member]
Fair value of plan assets	12,929	11,761
Fair Value, Level 3 [Member]
Fair value of plan assets
Debt Securities [Member]
Fair value of plan assets	12,929	11,761
Mutual Funds [Member]
Fair value of plan assets	18,924	20,819
Mutual Funds [Member] | Fair Value, Level 1 [Member]
Fair value of plan assets	18,924	20,819
Mutual Funds [Member] | Fair Value, Level 2 [Member]
Fair value of plan assets
Mutual Funds [Member] | Fair Value, Level 3 [Member]
Fair value of plan assets
Money Market Funds [Member]
Fair value of plan assets	2,769	3,388
Money Market Funds [Member] | Fair Value, Level 1 [Member]
Fair value of plan assets	2,769	3,388
Money Market Funds [Member] | Fair Value, Level 2 [Member]
Fair value of plan assets
Money Market Funds [Member] | Fair Value, Level 3 [Member]
Fair value of plan assets
Preferred Equity Securities [Member]
Fair value of plan assets		115
Preferred Equity Securities [Member] | Fair Value, Level 1 [Member]
Fair value of plan assets		115
Preferred Equity Securities [Member] | Fair Value, Level 2 [Member]
Fair value of plan assets
Preferred Equity Securities [Member] | Fair Value, Level 3 [Member]
Fair value of plan assets
Debt Securities [Member] | Fair Value, Level 1 [Member]
Fair value of plan assets
Debt Securities [Member] | Fair Value, Level 2 [Member]
Fair value of plan assets	12,929	11,761
Debt Securities [Member] | Fair Value, Level 3 [Member]
Fair value of plan assets

X

- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

+ References

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+ Details

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