Retirement Plans and Other Benefits - Estimated Future Benefit Payments (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Pension Benefits
Estimated Future Benefit Payments
2019	$ 188,492
2020	193,087
2021	198,471
2022	204,399
2023	211,346
Years 2024-2028	1,093,319
Other Benefits
Estimated Future Benefit Payments
2019	32,622
2020	34,199
2021	35,551
2022	36,673
2023	37,405
Years 2024-2028	$ 187,023

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Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 715
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Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fifth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fourth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in third fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in second fiscal year following latest fiscal year.

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