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Employee Benefit Plans (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Contribution to pension plan in excess of minimum required contribution	$ 0	$ 0	$ 0
Accumulated benefit obligation	$ 88,900	$ 76,800
Investment strategy, percentage in long-term growth	97.00%
Investment strategy, percentage in near-term benefit payments	3.00%
Percentage of Plan assets	99.00%	98.00%
Postretirement benefit plan, accrued liabilities	$ 108	$ 110
Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of portfolio invest directly or indirectly	35.00%
Percentage of remaining portfolio invest directly or indirectly	10.00%
Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of portfolio invest directly or indirectly	90.00%
Percentage of remaining portfolio invest directly or indirectly	65.00%
SERP [Member]
Defined Benefit Plan Disclosure [Line Items]
Unfunded pension liability	$ 1,300	1,700
Pension expense	$ 51	$ 366	$ 215
Investment Firm One [Member]
Defined Benefit Plan Disclosure [Line Items]
Portfolio management, controlled percentage	99.00%	98.00%
Defined Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Portfolio management, controlled percentage	1.00%	2.00%

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Amount of liability, recognized in statement of financial position, for defined benefit pension plan. Excludes other postretirement benefit plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
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Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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Amount of projected benefit obligation for defined benefit pension plan with accumulated benefit obligation in excess of plan assets.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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Amount of liability, recognized in statement of financial position, for pension, other postretirement and postemployment benefits.

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

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