- Changes in Accumulated Other Comprehensive Income (Loss) by Component, Net of Tax (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Increase (Decrease) In Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance	$ (57,190)
Other comprehensive loss before reclassifications	(23,864)
Amounts reclassified from accumulated other comprehensive income	(3,929)
Net current-period other comprehensive loss	(27,793)	94,985	9,255
Ending Balance	(84,983)	(57,190)
Gains/Losses on Cash Flow Hedges
Increase (Decrease) In Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance	423	(58,452)
Other comprehensive loss before reclassifications	(116)	(91)
Amounts reclassified from accumulated other comprehensive income	(220)	58,784
Net current-period other comprehensive loss	(336)	58,693
Spin-Off of WhiteWave		182
Ending Balance	87	423
Pension and Other Postretirement Benefits Items
Increase (Decrease) In Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance	(57,224)	(105,845)
Other comprehensive loss before reclassifications	(22,946)	56,541
Amounts reclassified from accumulated other comprehensive income	(3,709)	(9,472)
Net current-period other comprehensive loss	(26,655)	47,069
Spin-Off of WhiteWave		1,552
Ending Balance	(83,879)	(57,224)
Foreign Currency Items
Increase (Decrease) In Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance	(389)	(22,287)
Other comprehensive loss before reclassifications	(802)	(9,393)
Amounts reclassified from accumulated other comprehensive income		0
Net current-period other comprehensive loss	(802)	(9,393)
Spin-Off of WhiteWave		31,291
Ending Balance	(1,191)	(389)
Attributable to Parent
Increase (Decrease) In Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance		(186,584)
Other comprehensive loss before reclassifications		47,057
Amounts reclassified from accumulated other comprehensive income		49,312
Net current-period other comprehensive loss		96,369
Spin-Off of WhiteWave		33,025
Ending Balance		(57,190)
Non-controlling Interest
Increase (Decrease) In Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance		(3,683)
Other comprehensive loss before reclassifications		(1,378)
Amounts reclassified from accumulated other comprehensive income		(6)
Net current-period other comprehensive loss		(1,384)
Spin-Off of WhiteWave		5,067
Ending Balance		$ 0

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Other Comprehensive Income (Loss), Spinoff Transaction, Net Of Tax

+ References

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 14A

-URI http://asc.fasb.org/extlink&oid=28358780&loc=SL7669686-108580

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 11

-URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e637-108580

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 14

-URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e681-108580

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 31

-Article 5

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

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Amount after tax of reclassification adjustments of other comprehensive income (loss).

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