Details of Certain Consolidated Balance Sheet Captions (Retirement Obligations and Other Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Details of Certain Consolidated Balance Sheet Captions [Abstract]
Pension and postretirement benefits	$ 225,994	$ 199,603
Deferred taxes	84,345	149,633
Operating lease liabilities	176,246	151,523
Legal and environmental	101,203	99,744
Uncertain tax positions and other tax liabilities	50,259	42,086
Other	54,286	39,928
Retirement obligations and other liabilities	$ 692,333	$ 682,517

Details of Certain Consolidated Balance Sheet Captions [Abstract]

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Retirement Obligations, Other Liabilities, And Lease Liabilities

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Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable after twelve months or beyond the next operating cycle if longer.

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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences with jurisdictional netting.

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Amount recognized for uncertainty in income taxes classified as noncurrent.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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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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