Pension and Other Postretirement Benefit Plans Actuarial Assumptions Used to Determine the Actuarial Present Value of Projected Benefit Obligation and Net Periodic Pensions Costs (Details)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Retirement Benefits [Abstract]
Weighted average assumed discount rate	1.75%	2.00%
Expected long-term rate of return on plan assets	1.75%	2.00%
Weighted average rate of compensation increase	2.80%	2.90%

Defined Benefit Plan, Weighted Average Assumptions Used Calculating Benefit Obligation and Net Periodic Benefit Cost, Rate of Compensation Increase

No definition available.

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