Employee Benefit Plans (Assumptions Related to Calculation of Domestic Benefit Obligation (End of Period) and Determination of Net Periodic (Benefit) Cost (Beginning of Period)) (Details) |
12 Months Ended | |||
|---|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Minimum | ||||
| Defined Benefit Plan Disclosure [Line Items] | ||||
| Discount rate | 10.00% | |||
| Maximum | ||||
| Defined Benefit Plan Disclosure [Line Items] | ||||
| Discount rate | 90.00% | |||
| Pension Benefits | ||||
| Defined Benefit Plan Disclosure [Line Items] | ||||
| Discount rate | 3.65% | 4.15% | 4.50% | 4.10% |
| Rate of increase in compensation levels | 4.50% | 4.50% | 4.50% | 4.50% |
| Expected return on plan assets | 6.25% | 6.25% | 6.25% | 6.25% |
| Other Postretirement Benefits | ||||
| Defined Benefit Plan Disclosure [Line Items] | ||||
| Discount rate | 3.60% | 4.05% | 4.35% | 3.95% |
| Expected return on plan assets | 7.00% | 7.00% | 7.00% | 7.00% |
| Health care cost trend rates | 6.20% | 6.60% | 7.00% | 6.66% |
| Ultimate health care cost trend rate | 5.00% | 5.00% | 5.00% | 5.00% |