Amounts recognized in the consolidated balance sheets [Abstract]

$ 350,588

$ 345,633

Current Liabilities

6,701

6,888

Noncurrent Liabilities

83,619

145,047

Pension Plans, Defined Benefit [Member]

Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]

445,535

418,251

Service Cost

5,318

5,238

Interest Cost

17,826

19,986

Plan Amendments

510

Actuarial Loss (Gain)

(41,178)

38,329

Benefits Paid

(33,936)

(36,779)

Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]

393,565

445,535

Actual Return on Plan Assets

345,633

312,158

37,157

46,905

Employer contributions and benefit payments

1,734

23,349

Amounts recognized in the consolidated balance sheets [Abstract]

350,588

345,633

Current Liabilities

(1,772)

(1,775)

Noncurrent Liabilities

(41,205)

(98,127)

Funded Status of Plan

(42,977)

(99,902)

Other Postretirement Benefit Plans, Defined Benefit [Member]

Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]

52,033

65,195

Service Cost

284

Interest Cost

1,810

2,478

Plan Amendments

(6,045)

Actuarial Loss (Gain)

(2,692)

(4,878)

Benefits Paid

(3,902)

(5,001)

Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]

47,343

52,033

Actual Return on Plan Assets

Employer contributions and benefit payments

3,902

5,001

Amounts recognized in the consolidated balance sheets [Abstract]

Current Liabilities

(4,929)

(5,113)

Noncurrent Liabilities

(42,414)

(46,920)

Funded Status of Plan

$ (47,343)

$ (52,033)

The difference between fair value of plan assets at the end of the period and the fair value at the beginning of the period, adjusted for contributions and payments of benefits during the period, and after adjusting for taxes and other expenses, as applicable.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Actual Return on Plan Assets (Component of Net Periodic Postretirement Benefit Cost)

-URI http://asc.fasb.org/extlink&oid=6504192

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)(1)

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Actual Return on Plan Assets (Component of Net Periodic Pension Cost)

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Amount of gain (loss) related to change in benefit obligation resulting from changes in actuarial assumptions, for example, but not limited to, interest, mortality, employee turnover, salary, and temporary deviation from the substantive plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

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-URI http://asc.fasb.org/extlink&oid=6514294

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Subparagraph (a)(4)

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1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Glossary Projected Benefit Obligation

-URI http://asc.fasb.org/extlink&oid=6522206

Reference 3: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Postretirement Benefits

-URI http://asc.fasb.org/extlink&oid=6521376

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Topic 715

-SubTopic 30

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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The increase in the fair value of plan assets from contributions made by the employer.

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Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

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The funded status is measured as the difference between the fair value of plan assets and the benefit obligation. Will normally be the same as the net Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total.

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The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

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The amount of increase or decrease due to a change in the terms of an existing plan or the initiation of a new plan. A plan amendment may increase or decrease benefits, including those attributed to years of service already rendered.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Glossary Plan Amendment

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The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Glossary Service Cost (Component of Net Periodic Pension Cost)

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For a classified balance sheet, the amount recognized in balance sheet as a current liability associated with an underfunded defined benefit plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Glossary Current Liabilities

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This represents the noncurrent liability for underfunded plans recognized in the balance sheet that is associated with the defined benefit pension plans and other postretirement defined benefit plans.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Topic 210

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-Paragraph 1

-Subparagraph (SX 210.5-02.24)

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