Retirement Plans and Other Postretirement Benefits - Narrative (Details)	6 Months Ended
Jun. 30, 2020 USD ($)
Pension Benefits
Contributions
Minimum employer contributions for the next three years	$ 0
Maximum employer contributions for the next two years (up to)	100,000,000
Other Benefits
Contributions
Estimated future employer contributions in next three years	$ 0

Defined Benefit Plans Estimated Maximum Future Employer Contributions, Per Year Maximum Contribution For The Next Three Fiscal Years

No definition available.

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Period Type:	duration