Retirement Plans and Other Benefits - Estimated Future Benefit Payments (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Pension Benefits
Estimated Future Benefit Payments
2020	$ 199,395
2021	201,597
2022	206,618
2023	213,208
2024	218,150
Years 2025-2029	1,111,171
Other Benefits
Estimated Future Benefit Payments
2020	31,531
2021	32,777
2022	33,566
2023	34,415
2024	34,468
Years 2025-2029	$ 174,607

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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
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
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-Subparagraph (f)
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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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