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Defined Pension Plans (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Defined Benefit Plan Disclosure [Line Items]
Pension period			30 years
Defined Benefit Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Pension costs	$ 1,103	$ 1,178	$ 3,159	$ 3,543
Unfunded Supplemental Executive Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Pension costs	$ 145	$ 195	$ 435	$ 586

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- Definition

Defined Benefit Plan, Pension Period

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount of cost (reversal of cost) for pension benefits. Excludes other postretirement benefits.

+ References

No definition available.

+ Details

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- Details

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- Details

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