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Benefit Plans - Contributions to Pension and Other Postretirement Benefit Plans (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020 | Jul. 01, 2019
--- | --- | --- | ---
Qualified Plan (ERP) |  |  |
Benefit Plans |  |  |
Benefit accruals for the company's employees | $ 0 |  |
Pension Plan |  |  |
Benefit Plans |  |  |
Benefit accruals for the company's employees | (97,784) | $ (104,597) |
Pension Plan | Qualified Plan (ERP) |  |  |
Benefit Plans |  |  |
Expected contributions in 2021 | 0 |  |
Pension Plan | Nonqualified Plan |  |  |
Benefit Plans |  |  |
Expected contributions in 2021 | 200 |  |
SERP and Directors' Plan |  |  |
Benefit Plans |  |  |
Benefit accruals for the company's employees |  |  | $ 0
Expected contributions in 2021 | 0 |  |
Other Benefits | Nonqualified Plan |  |  |
Benefit Plans |  |  |
Expected contributions in 2021 | $ 1,200 |  |

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- Definition Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=123450688&loc=d3e4587-114921 + Details
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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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=123453770&loc=d3e1703-114919 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=123450688&loc=d3e4179-114921 + Details
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