Pension and Postretirement Plans (Consolidated Balance Sheet) (Details 2) - USD ($) $ in Thousands |
Dec. 31, 2017 |
Dec. 31, 2016 |
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Defined Benefit Plan Disclosure [Line Items] | ||
Noncurrent asset | $ 1,056,777 | $ 881,593 |
Pension Plans [Member] | ||
Defined Benefit Plan Disclosure [Line Items] | ||
Noncurrent asset | 1,056,777 | 881,593 |
Current liability | 0 | 0 |
Noncurrent liability | 0 | 0 |
Recognized asset (liability) | 1,056,777 | 881,593 |
Supplemental Executive Retirement Plan (SERP) [Member] | ||
Defined Benefit Plan Disclosure [Line Items] | ||
Noncurrent asset | 0 | 0 |
Current liability | (5,838) | (5,580) |
Noncurrent liability | (104,244) | (100,946) |
Recognized asset (liability) | (110,082) | (106,526) |
Other Postretirement Plans [Member] | ||
Defined Benefit Plan Disclosure [Line Items] | ||
Current liability | (1,920) | (2,312) |
Noncurrent liability | (20,865) | (21,859) |
Recognized asset (liability) | $ (22,785) | $ (24,171) |
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- Definition Amount of asset (liability), recognized in statement of financial position, for defined benefit pension and other postretirement plans. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as current. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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