Variable Interest Entities and Preferred Securities of Subsidiaries - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended	9 Months Ended				1 Months Ended			12 Months Ended				12 Months Ended	3 Months Ended		1 Months Ended	9 Months Ended		12 Months Ended	9 Months Ended	1 Months Ended			3 Months Ended	1 Months Ended	3 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	3 Months Ended		3 Months Ended
	Oct. 31, 2007 acre	Sep. 30, 2012	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011	Dec. 31, 2007	May 31, 2011 2002 Financing Entities	Mar. 16, 2011 2001 Financing Entities	Oct. 31, 2007 Variable Interest Entity, Not Primary Beneficiary	Dec. 31, 2006 Variable Interest Entity, Not Primary Beneficiary	Sep. 30, 2012 Variable Interest Entity, Not Primary Beneficiary Class B Interests In Entities	Dec. 31, 2011 Variable Interest Entity, Not Primary Beneficiary Class B Interests In Entities	Dec. 31, 2006 Variable Interest Entity, Not Primary Beneficiary Class B Interests In Entities	Dec. 31, 2006 Timber Notes acre	Sep. 30, 2012 Timber Notes Royal Bank Of Scotland Group Plc	Oct. 07, 2011 Timber Notes Royal Bank Of Scotland Group Plc	Jun. 30, 2012 Timber Notes BNP Paribas	Sep. 30, 2012 Timber Notes BNP Paribas	Jun. 21, 2012 Timber Notes BNP Paribas	Dec. 31, 2001 Monetized Notes and Cash Variable Interest Entity, Not Primary Beneficiary	Sep. 30, 2012 2001 Monetized Notes	Mar. 16, 2011 2001 Monetized Notes Variable Interest Entity, Not Primary Beneficiary	Sep. 30, 2012 Preferred Securities Of Subsidiaries	Mar. 31, 2003 Preferred Securities Of Subsidiaries acre	Mar. 31, 2011 Preferred Securities Of Subsidiaries 2001 Financing Entities	May 31, 2012 2002 Monetized Notes	Mar. 31, 2012 2002 Monetized Notes	Sep. 30, 2012 2002 Monetized Notes	Dec. 31, 2011 2002 Monetized Notes	Sep. 30, 2012 2007 Monetized Notes	Sep. 30, 2012 Monetized Notes Barclays Plc	Jun. 21, 2012 Monetized Notes Barclays Plc	Sep. 30, 2012 Financial Assets	Sep. 30, 2012 Financial Liabilities
Variable Interest Entity [Line Items]
Forestlands acreage sales														5,600,000
Amount of consideration received									$ 2,380,000,000	$ 4,800,000,000
Contribution of Class A interests in the Borrower Entities to other newly formed entities in December 2006										200,000,000
Contribution of International Paper promissory notes, to other newly formed entities										400,000,000
Class B interests held in entities in December 2006													5,000,000,000
Letters of credit downgrade period of replacement			Within 60 days														Within 60 days	60 days												within 30 days
Entities acquired International Paper debt obligations for cash										4,800,000,000										1,000,000,000
International Paper debt obligations held by the Entities		10,500,000,000	10,500,000,000							5,200,000,000	5,200,000,000
Interest, offset against related debt obligations of the entities											5,200,000,000
Remainder of the borrowing included in long-term debt		10,048,000,000	10,048,000,000		9,189,000,000	2,140,000,000					93,000,000	92,000,000
Additional debt included in notes payable and current maturities		413,000,000	413,000,000		719,000,000						66,000,000	38,000,000
Letters of credit issued that support Timber Notes	2,380,000,000															797,000,000			707,000,000													500,000,000
Replacement fees incurred															5,000,000																6,000,000
The percent of letters of credit supporting Timber Notes and Monetized Note that are cash collateralized		100.00%	100.00%
Transferred notes (the Monetized Notes) and cash to entities in exchange for preferred interests																				1,000,000,000
Long-term notes, maturity term																					10 years
Amount of consideration received from sale of notes																						499,000,000
Purchase of preferred interest from external third party																									21,000,000
Percentage of interest in financing entities							100.00%	100.00%
Payments of capital distribution							51,000,000
Notes matured																										141,000,000	111,000,000		191,000,000
Outstanding debt included in notes payble and current maturities																													158,000,000
Increase (decrease) in accounts and notes receivables																												(252,000,000)
Decrease notes payable and current maturities of long-term debt																												(158,000,000)
Decrease in deferred tax liabilities due to sale of forestlands																												(67,000,000)
Forestlands acres held in United States initially by Southeast timber	1,550,000
Fair value of notes receivable as of acquisition date	2,090,000,000
Decrease in financial assets		(292,000,000)
Fair value of notes reveivable as of 9/30/2012		2,160,000,000	2,160,000,000
Fair value of financial assets as of acquisition date						2,030,000,000
Fair value of debt as of 9/30/2012		2,080,000,000	2,080,000,000
Decrease in nonrecourse financial liabilities		(110,000,000)
Purchase accounting adjustments																																	292,000,000	(110,000,000)
Decrease in financial assets from deconsolidation of SPE		92,000,000
Preferred third-party interest, included in noncontrolling interest		339,000,000	339,000,000		340,000,000																			150,000,000
Forestlands acres held in United States initially by Southeast timber																								1,500,000
Distributions under preferred securities to third party investors			4,000,000	4,000,000
Preferred securities issued to a private investor with future dividend payments based on LIBOR in March 2003																							150,000,000
Noncontrolling interest decreased from deconsolidation		$ (92,000,000)