Interim Pension and Other Postretirement Benefits (Details) (USD $)	0 Months Ended	3 Months Ended
Oct. 02, 2013	Dec. 31, 2014	Dec. 31, 2013
Pension Benefits [Member]
Components of net periodic pension cost [Abstract]
Service Cost		$ 5,051,000	$ 4,738,000
Interest Cost		6,699,000	6,824,000
Expected return on assets		(6,436,000)	(5,901,000)
Amortization of transition (asset)/obligation		0	0
Amortization of prior service (credit)/cost		(49,000)	(34,000)
Amortization of actuarial (gain) loss		3,917,000	3,932,000
Settlement loss	4,500,000	0	4,539,000
Net periodic pension cost		9,182,000	14,098,000
Defined Benefit Plan Weighted Average Assumptions Used In Calculating Net Periodic Benefit Cost Abstract
Discount Rate		4.43%	4.95%
Rate of compensation increase		3.50%	3.50%
Expected return on plan assets		7.25%	7.25%
Current Year Benefit Plan Contributions [Abstract]
Benefit Payment	16,800,000
Other Benefits [Member]
Components of net periodic pension cost [Abstract]
Service Cost		3,896,000	4,196,000
Interest Cost		3,596,000	3,988,000
Expected return on assets		(1,608,000)	(1,292,000)
Amortization of transition (asset)/obligation		68,000	68,000
Amortization of prior service (credit)/cost		(411,000)	(363,000)
Amortization of actuarial (gain) loss		0	158,000
Settlement loss		0	0
Net periodic pension cost		5,541,000	6,755,000
Defined Benefit Plan Weighted Average Assumptions Used In Calculating Net Periodic Benefit Cost Abstract
Discount Rate		4.43%	4.95%
Expected return on plan assets		4.60%	4.60%
Current Year Benefit Plan Contributions [Abstract]
Contributions Actual		5,600,000
Other Benefits [Member] \| Minimum [Member]
Current Year Benefit Plan Contributions [Abstract]
Defined Benefit Plan, Expected Contributions in Current Fiscal Year		20,000,000
Other Benefits [Member] \| Maximum [Member]
Current Year Benefit Plan Contributions [Abstract]
Defined Benefit Plan, Expected Contributions in Current Fiscal Year		$ 25,000,000

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The amount of gains or losses recognized in net periodic benefit cost.

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- Definition

The amount of the prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation.

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The amount of the transition obligation or asset recognized in net periodic benefit cost.

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- Definition

The interest rate used to adjust for the time value of money.

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- Definition

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Long-Term Rate of Return on Plan Assets

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (k)(3)

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- Definition

Expected rate of compensation increases (for pay-related plans).

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- Definition

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

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Amount of the employer's best estimate of contributions expected to be paid to the plan in the current fiscal period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e2709-114920

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- Definition

An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Return on Plan Assets

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-Topic 715

-SubTopic 60

-Glossary Expected Return on Plan Assets

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-Subparagraph (h)(3)

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- Definition

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 total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

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- Definition

Amount of net gain (loss) recognized in net periodic benefit cost as a result of an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include, but are not limited to, lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contracts to cover vested benefits.

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

-Publisher FASB

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-Subparagraph (a)(1)

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- Definition

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

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-Name Accounting Standards Codification

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

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The amount of decrease that relates to an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include (a) making lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and (b) purchasing nonparticipating annuity contracts.

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