Employee Benefit Plans (Change in Plan Assets and Funded Status) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Pension Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Benefit Obligation, Beginning Balance	$ 54,319	$ 53,293
Service cost
Interest cost	1,712	1,786
Actuarial loss (gain)	(4,037)	2,599
Benefits paid	(3,404)	(3,629)
Lump-sum settlement payment
Settlement gain
Plan curtailment
Special termination benefits		270
Defined Benefit Plan, Benefit Obligation, Ending Balance	48,590	54,319
Plan assets - Beginning of year	48,556	46,472
Return on plan assets	(2,403)	5,713
Employer contributions
Benefits paid	(3,404)	(3,629)
Lump-sum settlement payment
Plan assets at fair value - End of year	42,749	48,556
Funded status of plans - End of year	(5,841)	(5,763)
Postretirement Benefit Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Benefit Obligation, Beginning Balance	5,956	6,172
Service cost	33	48
Interest cost	186	199
Actuarial loss (gain)	(237)	(74)
Benefits paid	(568)	(539)
Lump-sum settlement payment
Settlement gain
Plan curtailment
Special termination benefits		150
Defined Benefit Plan, Benefit Obligation, Ending Balance	5,370	5,956
Plan assets - Beginning of year
Return on plan assets
Employer contributions	568	539
Benefits paid	(568)	(539)
Lump-sum settlement payment
Plan assets at fair value - End of year
Funded status of plans - End of year	$ (5,370)	$ (5,956)

Cash payment for settlement of postretirement benefit plan obligation.

No definition available.

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- Definition

Amount of payment, which decreases plan assets of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract.

+ References

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Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

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Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

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Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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- Definition

Amount of (increase) decrease in benefit obligation of defined benefit plan from event reducing expected years of future service of present employees or eliminating accrual of benefits for some or all future services of present employees.

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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.

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- Definition

Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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Amount of cost recognized for passage of time related to defined benefit plan.

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Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Amount of (increase) decrease to benefit obligation of defined benefit plan from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Includes, but is not limited to, lump-sum cash payment to participant in exchange for right to receive specified benefits, purchase of nonparticipating annuity contract and change from remeasurement.

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- Definition

Amount of increase in benefit obligation for benefits provided to employees payable from defined benefit plan or payable upon retirement.

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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.

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No definition available.

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