Pension Plans (Expected Future Benefits) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Qualified Pension Plan
Defined Benefit Plan Disclosure [Line Items]
2020	$ 39,368
2021	40,664
2022	41,966
2023	43,107
2024	44,127
2025-2029	$ 225,251
Discount rate	3.14%	4.17%
Discount rate for calculating net periodic benefit cost	4.17%	3.50%
Expected return on plan assets	7.50%	7.50%
SERP
Defined Benefit Plan Disclosure [Line Items]
2020	$ 528
2021	2,554
2022	494
2023	474
2024	451
2025-2029	$ 1,863
Discount rate	2.76%	3.88%
Discount rate for calculating net periodic benefit cost	3.88%	3.15%

Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

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 (k)(1)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

+ Details

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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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- Definition

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

+ 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 (k)(3)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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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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Period Type:	duration

- Definition

Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

+ References