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Employee Benefit Plans (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Contribution to pension plan in excess of minimum required contribution	$ 0	$ 0	$ 0
Accumulated benefit obligation	$ 76,800	63,300
Investment strategy, percentage in long-term growth	97.00%
Investment strategy, percentage in near-term benefit payments	3.00%
Maximum percentage of securities purchasing allowed of the portfolio at any time	5.00%
Maximum market value purchase percentage allowed of any one issuer	8.00%
Percentage of Plan assets	98.00%
Postretirement benefit plan, accrued liabilities	$ 110	109
Estimated future net loss for the plan that will be amortized from accumulated other comprehensive income	$ 1,300	$ 34
Commercial Mortgage Back Securities And Assets Backed Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Maximum percentage of securities purchasing allowed of the portfolio at any time	10.00%
Securities Less Than Aquality [Member]
Defined Benefit Plan Disclosure [Line Items]
Maximum percentage of securities purchasing allowed of the portfolio at any time	13.00%
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%
Portfolio Concentration Commingled Trust Fund1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of Plan assets		15.00%
Portfolio Concentration Commingled Trust Fund2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of Plan assets		6.00%
Portfolio Concentration Short Term Investment Fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of Plan assets		6.00%
SERP [Member]
Defined Benefit Plan Disclosure [Line Items]
Unfunded pension liability	$ 1,700	$ 1,700
Pension expense	$ 366	$ 215	$ 194
Investment Firm One [Member]
Defined Benefit Plan Disclosure [Line Items]
Portfolio management, controlled percentage	98.00%	62.00%
Defined Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Portfolio management, controlled percentage	2.00%	2.00%
Investment Firm Two [Member]
Defined Benefit Plan Disclosure [Line Items]
Portfolio management, controlled percentage		36.00%

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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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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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