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Employee Benefit Plans (Details) - Narrative $ in Thousands | 12 Months Ended
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Dec. 31, 2021 USD ($) years period shares | Dec. 31, 2020 USD ($) shares | Dec. 31, 2019 USD ($) shares
Employee Benefit [Line Items] |  |  |
Number of Look-back Period Under Employee Stock Purchase Plan | period | 2 |  |
Look-back Period Under Employee Stock Purchase Plan | 6 months |  |
Discount On Common Stock Under Employee Stock Purchase Plan, Percent | 10.00% |  |
Stock Issued During Period, Shares, Employee Stock Purchase Plans | shares | 63,586 | 79,297 | 57,201
Stock Issued During Period, Value, Employee Stock Purchase Plan | $ 2,300 | $ 2,200 | $ 2,100
Shares Available For Purchase Under Employee Stock Purchase Plan | shares | 160,273 |  |
Pension Plan |  |  |
Employee Benefit [Line Items] |  |  |
Deferred Compensation Arrangement with Individual, Contributions by Employer | $ 4,000 | 3,800 | 3,500
Pension Plan | Minimum |  |  |
Employee Benefit [Line Items] |  |  |
Deferred Compensation Arrangement with Individual, Eligible Age | years | 18 |  |
Pension Plan | Maximum |  |  |
Employee Benefit [Line Items] |  |  |
Deferred Compensation Arrangement with Individual, Contribution Requirements, Percent Of Each Employee Compensation | 3.00% |  |
Deferred Profit Sharing |  |  |
Employee Benefit [Line Items] |  |  |
Deferred Compensation Arrangement with Individual, Contribution To Plan By Employee, Percent Of Eligible Compensation | 75.00% |  |
Deferred Compensation Arrangement with Individual, Contribution Requirements, Matching Percent | 50.00% |  |
Deferred Compensation Arrangement with Individual, Contributions by Employer | $ 7,700 | 8,100 | 7,300
Deferred Profit Sharing | Minimum |  |  |
Employee Benefit [Line Items] |  |  |
Deferred Compensation Arrangement with Individual, Eligible Age | years | 18 |  |
Deferred Profit Sharing | Maximum |  |  |
Employee Benefit [Line Items] |  |  |
Deferred Compensation Arrangement with Individual, Contribution Requirements, Percent Of Each Employee Compensation | 3.00% |  |
ESP Plan |  |  |
Employee Benefit [Line Items] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Discount from Market Price, Purchase Date | 90.00% |  |
Unit Plans |  |  |
Employee Benefit [Line Items] |  |  |
Deferred Compensation Arrangement with Individual, Vesting Period | 10 years |  |
Deferred Compensation Arrangement with Individual, Benefit Period | 10 years |  |
Deferred Compensation Arrangement with Individual, Recorded Liability | $ 3,800 | 4,000 |
Deferred Compensation Arrangement with Individual, Compensation Expense | $ 363 | $ 488 | $ 415
SERP |  |  |
Employee Benefit [Line Items] |  |  |
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate | 2.84% | 2.51% |
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Normal Retirement Age | years | 65 |  |
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Annual Cost Of Living Benefit Adjustment | 2.00% |  |

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