Details of Certain Consolidated Balance Sheet Captions (Retirement Obligations and Other Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Details of Certain Consolidated Balance Sheet Captions [Abstract]
Pension and postretirement benefits	$ 203,640	$ 216,772
Deferred taxes	156,276	20,086
Legal and environmental	25,996	32,546
Uncertain tax positions and other tax liabilities	72,711	93,524
Other	38,331	44,911
Retirement obligations and other liabilities	$ 496,954	$ 407,839

Details of Certain Consolidated Balance Sheet Captions [Abstract]

No definition available.

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- Definition

For a classified balance sheet, the carrying amount as of the balance sheet date of the portion of the obligations recognized for the various post employment and postretirement benefits provided to former or inactive employees, their beneficiaries, and covered dependents that is payable after one year (or beyond the operating cycle if longer. Aggregate carrying amount, as of the balance sheet date, of noncurrent obligations not separately disclosed in the balance sheet due to materiality considerations. Noncurrent liabilities are expected to be paid after one year (or the normal operating cycle, if longer).

+ References

No definition available.

+ Details

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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- Definition

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

+ References

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- Definition

Amount recognized for uncertainty in income taxes classified as noncurrent.

+ References

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- Definition

Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer.

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- Definition

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

+ References

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