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Employee Benefit Plans (Actual Plan Asset Allocations) (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 55,971 | $ 50,829
Defined Benefit Plan, Actual Plan Asset Allocations | 100.00% | 100.00%
Common stock shares included in large cap equities | 194,124 |
Fair Value, Inputs, Level 1 [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 39,804 | $ 34,125
Fair Value, Inputs, Level 2 [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | 16,167 | 16,704
Cash and Cash Equivalents [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 2,312 | $ 247
Defined Benefit Plan, Actual Plan Asset Allocations | 4.10% | 0.50%
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 2,312 | $ 247
Fixed Income Securities [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 22,423 | $ 23,145
Defined Benefit Plan, Actual Plan Asset Allocations | 40.10% | 45.50%
Fixed Income Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 6,256 | $ 6,441
Fixed Income Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | 16,167 | 16,704
U.S. Government and Agencies [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 298 | $ 1,904
Defined Benefit Plan, Actual Plan Asset Allocations | 0.60% | 3.70%
U.S. Government and Agencies [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 298 | $ 1,904
Taxable Municipal Bonds and Notes [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 4,215 | $ 4,555
Defined Benefit Plan, Actual Plan Asset Allocations | 7.50% | 8.90%
Taxable Municipal Bonds and Notes [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 4,215 | $ 4,555
Corporate Bonds and Notes [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 10,681 | $ 9,588
Defined Benefit Plan, Actual Plan Asset Allocations | 19.10% | 18.90%
Corporate Bonds and Notes [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 10,681 | $ 9,588
Preferred Stock [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 973 | $ 657
Defined Benefit Plan, Actual Plan Asset Allocations | 1.70% | 1.30%
Preferred Stock [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 973 | $ 657
Fixed Income Mutual Funds [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 6,256 | $ 6,441
Defined Benefit Plan, Actual Plan Asset Allocations | 11.20% | 12.70%
Fixed Income Mutual Funds [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 6,256 | $ 6,441
Equity Securities [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 31,236 | $ 27,437
Defined Benefit Plan, Actual Plan Asset Allocations | 55.80% | 54.00%
Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 31,236 | $ 27,437
Large Cap [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 24,886 | $ 21,460
Defined Benefit Plan, Actual Plan Asset Allocations | 44.50% | 42.20%
Large Cap [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 24,886 | $ 21,460
Mid Cap [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 1,511 | $ 1,660
Defined Benefit Plan, Actual Plan Asset Allocations | 2.70% | 3.30%
Mid Cap [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 1,511 | $ 1,660
Small Cap [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 477 | $ 1,009
Defined Benefit Plan, Actual Plan Asset Allocations | 0.80% | 2.00%
Small Cap [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 477 | $ 1,009
International [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 4,362 | $ 3,308
Defined Benefit Plan, Actual Plan Asset Allocations | 7.80% | 6.50%
International [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 4,362 | $ 3,308

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