| **Employee Retirement Benefits (Weighted-Average Assumptions Used) (Details)** | 12 Months Ended |
|--------------------------------------------------------------------------------|-----------------|
||
| Benefit Obligations | Pension Plan                                             |            |   |   |
| **Schedule of Benefit Obligations Weighted Average Assumptions**               |            |   |   |
| Discount rate                                                                  | 3.73%           | 4.30% |   |
| Benefit Obligations | Pension Plan | Minimum                                   |            |   |   |
| **Schedule of Benefit Obligations Weighted Average Assumptions**               |            |   |   |
| Rate of compensation increase                                                  | 2.75%           | 2.75% |   |
| Benefit Obligations | Pension Plan | Maximum                                   |            |   |   |
| **Schedule of Benefit Obligations Weighted Average Assumptions**               |            |   |   |
| Rate of compensation increase                                                  | 3.25%           | 3.25% |   |
| Benefit Obligations | Supplemental Employee Retirement Plan                    |            |   |   |
| **Schedule of Benefit Obligations Weighted Average Assumptions**               |            |   |   |
| Discount rate                                                                  | 3.61%           | 4.10% |   |
| Benefit Obligations | Supplemental Employee Retirement Plan | Minimum          |            |   |   |
| **Schedule of Benefit Obligations Weighted Average Assumptions**               |            |   |   |
| Rate of compensation increase                                                  | 2.75%           | 2.75% |   |
| Benefit Obligations | Supplemental Employee Retirement Plan | Maximum          |            |   |   |
| **Schedule of Benefit Obligations Weighted Average Assumptions**               |            |   |   |
| Rate of compensation increase                                                  | 3.25%           | 3.25% |   |
| Net Periodic Benefit Cost | Pension Plan                                       |            |   |   |
| **Schedule of Benefit Obligations Weighted Average Assumptions**               |            |   |   |
| Discount rate                                                                  | 4.30%           | 4.55% | 4.25% |
| Expected return on plan assets                                                 | 7.25%           | 7.25% | 7.25% |
| Net Periodic Benefit Cost | Pension Plan | Minimum                             |            |   |   |
| **Schedule of Benefit Obligations Weighted Average Assumptions**               |            |   |   |
| Rate of compensation increase                                                  | 2.75%           | 2.75% | 2.75% |
| Net Periodic Benefit Cost | Pension Plan | Maximum                             |            |   |   |
| **Schedule of Benefit Obligations Weighted Average Assumptions**               |            |   |   |
| Rate of compensation increase                                                  | 3.25%           | 3.25% | 3.25% |
| Net Periodic Benefit Cost | Supplemental Employee Retirement Plan              |            |   |   |
| **Schedule of Benefit Obligations Weighted Average Assumptions**               |            |   |   |
| Discount rate                                                                  | 4.10%           | 4.30% | 4.05% |
| Net Periodic Benefit Cost | Supplemental Employee Retirement Plan | Minimum    |            |   |   |
| **Schedule of Benefit Obligations Weighted Average Assumptions**               |            |   |   |
| Rate of compensation increase                                                  | 2.75%           | 2.75% | 2.75% |
| Net Periodic Benefit Cost | Supplemental Employee Retirement Plan | Maximum    |            |   |   |
| **Schedule of Benefit Obligations Weighted Average Assumptions**               |            |   |   |
| Rate of compensation increase                                                  | 3.25%           | 3.25% | 3.25% |

| X                                                                                                                                                                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Schedule of Benefit Obligations Weighted Average Assumptions [Line Items]
+ References
No definition available.
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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
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(3) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Weighted average rate of compensation increase used to determine net periodic benefit cost of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(2) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920
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