Retirement Plans and Other Benefits - Amounts Recognized on the Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Amounts recognized on the Consolidated Balance Sheets
Noncurrent asset	$ 90,570	$ 46,906
Pension Benefits
Amounts recognized on the Consolidated Balance Sheets
Noncurrent asset	0	0
Current liability	(14,578)	(13,980)
Noncurrent liability	(280,185)	(443,170)
Net amount recognized	(294,763)	(457,150)
Other Benefits
Amounts recognized on the Consolidated Balance Sheets
Noncurrent asset	90,570	46,906
Current liability	0	0
Noncurrent liability	0	0
Net amount recognized	$ 90,570	$ 46,906

Amount of asset (liability), recognized in statement of financial position, for defined benefit pension and other postretirement plans.

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- Definition

Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

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Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as current.

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Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as noncurrent.

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