Benefit Plans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan annual benefit after retirement or death period	15 years
Pension and other postretirement benefit contributions, Total	$ 5,276	$ 5,229
Pension and other postretirement benefit expense, Total	329	375	$ 325
Defined benefit plan, Benefits paid	$ 281	$ 296	$ 254
Percentage Of Salary Deferred For Tax Deferred Savings Plan Maximum	15.00%
Defined Contribution Plan, Employers Matching Contribution, Annual Vesting Percentage	6.00%
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent	95.00%	75.00%	75.00%
Defined contribution plan employer matching contribution vesting period	5 years
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 1,134	$ 934	$ 745
Premium Life Insurance Policies [Member]
Defined Benefit Plan Disclosure [Line Items]
Cash Surrender Value of Life Insurance	42,528	41,561
Deferred Compensation Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Cash Surrender Value of Life Insurance	$ 7,989	$ 6,592

Defined contribution plan annual benefit after retirement or death period.

No definition available.

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- Definition

Defined contribution plan employer matching contribution vesting period.

+ References

No definition available.

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- Definition

Percentage of salary deferred for tax deferred savings plan maximum.

+ References

No definition available.

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- Definition

Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 4
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=118951113&loc=d3e6812-107765

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)(6)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 60
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964

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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.

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

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- Definition

Percentage of employer's matching contributions to a defined contribution plan that vests in a given year.

+ References

No definition available.

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- Definition

Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

+ References

No definition available.

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- Definition

Amount of cash outflow for pension and other postretirement benefits. Includes, but is not limited to, employer contribution to fund plan asset and payment to retiree.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3536-108585

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- Definition

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

+ References

No definition available.

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