Plum Creek Timber (PCL) 10-Q 8 Nov 13 2013 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information Document	9 Months Ended
	Sep. 30, 2013	Nov. 04, 2013
Entity Information [Line Items]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	30-Sep-13	'
Document Fiscal Year Focus	'2013	'
Document Fiscal Period Focus	'Q3	'
Entity Registrant Name	'PLUM CREEK TIMBER CO INC	'
Entity Central Index Key	'0000849213	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Large Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	176,909,909
PLUM CREEK TIMBERLANDS L P [Member]	'	'
Entity Information [Line Items]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	30-Sep-13	'
Document Fiscal Year Focus	'2013	'
Document Fiscal Period Focus	'Q3	'
Entity Registrant Name	'Plum Creek Timberlands LP	'
Entity Central Index Key	'0001296350	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Non-accelerated Filer	'

Consolidated_Statements_of_Inc

Consolidated Statements of Income (USD $)	3 Months Ended		9 Months Ended
In Millions, except Per Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Interest Expense, net:	'	'	'	'
Net Income	$72	$59	$174	$124
PER SHARE AMOUNTS:	'	'	'	'
Net Income per Share-Basic	$0.44	$0.36	$1.06	$0.77
Net Income per Share-Diluted	$0.44	$0.36	$1.06	$0.76
Weighted-Average Number of Shares Outstanding	'	'	'	'
-Basic	163	161.5	162.7	161.5
-Diluted	163.4	161.9	163.2	161.8
PLUM CREEK TIMBER CO INC [Member]	'	'	'	'
REVENUES:	'	'	'	'
Timber	171	168	487	480
Real Estate	96	96	227	243
Manufacturing	94	85	279	246
Other	5	5	16	16
Total Revenues	366	354	1,009	985
COSTS AND EXPENSES:	'	'	'	'
Timber	132	130	364	374
Real Estate	31	40	83	124
Manufacturing	80	74	237	217
Other	1	0	3	1
Total Cost of Goods Sold	244	244	687	716
Selling, General and Administrative	28	31	89	86
Total Costs and Expenses	272	275	776	802
Other Operating Income (Expense), Net	-3	0	-2	1
Operating Income	91	79	231	184
Equity Earnings from Timberland Venture	16	14	47	42
Interest Expense, net:	'	'	'	'
Interest Expense (Debt Obligations to Unrelated Parties)	20	21	61	61
Interest Expense (Note Payable to Timberland Venture)	14	14	43	43
Total Interest Expense, net	34	35	104	104
Income before Income Taxes	73	58	174	122
Provision (Benefit) for Income Taxes	1	-1	0	-2
Net Income	72	59	174	124
PER SHARE AMOUNTS:	'	'	'	'
Net Income per Share-Basic	$0.44	$0.36	$1.06	$0.77
Net Income per Share-Diluted	$0.44	$0.36	$1.06	$0.76
Dividends Declared - per Common Share Outstanding	$0.44	$0.42	$1.30	$1.26
Weighted-Average Number of Shares Outstanding	'	'	'	'
-Basic	163	161.5	162.7	161.5
-Diluted	163.4	161.9	163.2	161.8
PLUM CREEK TIMBERLANDS L P [Member]	'	'	'	'
REVENUES:	'	'	'	'
Timber	171	168	487	480
Real Estate	96	96	227	243
Manufacturing	94	85	279	246
Other	5	5	16	16
Total Revenues	366	354	1,009	985
COSTS AND EXPENSES:	'	'	'	'
Timber	132	130	364	374
Real Estate	31	40	83	124
Manufacturing	80	74	237	217
Other	1	0	3	1
Total Cost of Goods Sold	244	244	687	716
Selling, General and Administrative	28	31	89	86
Total Costs and Expenses	272	275	776	802
Other Operating Income (Expense), Net	-3	0	-2	1
Operating Income	91	79	231	184
Equity Earnings from Timberland Venture	16	14	47	42
Interest Expense, net:	'	'	'	'
Total Interest Expense, net	20	21	61	61
Income before Income Taxes	87	72	217	165
Provision (Benefit) for Income Taxes	1	-1	0	-2
Net Income before Allocation to Series T-1 Preferred Interest and Partners	86	73	217	167
Net Income Allocable to Series T-1 Preferred Interest	-14	-14	-43	-43
Net Income	$72	$59	$174	$124

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (USD $)	3 Months Ended				9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Net Income	$72	'	'	$59	$174	$124
PLUM CREEK TIMBER CO INC [Member]	'	'	'	'	'	'
Net Income	72	46	56	59	174	124
Defined Benefit Pension Plans [Abstract]	'	'	'	'	'	'
Amortization of Actuarial Loss Reclassified to Pension Expense	1	'	'	1	3	3
Unrealized Gains (Losses) on Grantor Trust Assets [Abstract]	'	'	'	'	'	'
Unrealized Holding Gain (Losses)	-1	'	'	1	2	2
Other Comprehensive Income (Loss), before Tax	0	'	'	2	5	5
Other Comprehensive Income (Loss), Tax	0	'	'	0	0	0
Other Comprehensive Income (Loss), net of tax	0	2	3	2	5	5
Total Comprehensive Income	72	'	'	61	179	129
PLUM CREEK TIMBERLANDS L P [Member]	'	'	'	'	'	'
Net Income	72	'	'	59	174	124
Net Income before Allocation to Series T-1 Preferred Interest and Partners	86	61	70	73	217	167
Defined Benefit Pension Plans [Abstract]	'	'	'	'	'	'
Amortization of Actuarial Loss Reclassified to Pension Expense	1	'	'	1	3	3
Unrealized Gains (Losses) on Grantor Trust Assets [Abstract]	'	'	'	'	'	'
Unrealized Holding Gain (Losses)	-1	'	'	1	2	2
Other Comprehensive Income (Loss), before Tax	0	'	'	2	5	5
Other Comprehensive Income (Loss), Tax	0	'	'	0	0	0
Other Comprehensive Income (Loss), net of tax	0	2	3	2	5	5
Total Comprehensive Income	$86	'	'	$75	$222	$172

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
PLUM CREEK TIMBER CO INC [Member]	'	'	'	'
Current Assets:	'	'	'	'
Cash and Cash Equivalents	$439	'	'	$356
Accounts Receivable	35	'	'	22
Inventories	53	'	'	49
Deferred Tax Asset	8	'	'	7
Assets Held for Sale	38	'	'	61
Other Current Assets	17	'	'	13
Total Current Assets	590	'	'	508
Timber and Timberlands, net	3,395	'	'	3,363
Mineral Rights, net	242	'	'	87
Property, Plant and Equipment, net	118	'	'	127
Equity Investment in Timberland Venture	195	'	'	204
Deferred Tax Asset	19	'	'	19
Investment in Grantor Trusts (at Fair Value)	42	'	'	39
Other Assets	30	'	'	37
Total Assets	4,631	'	'	4,384
Current Liabilities:	'	'	'	'
Current Portion of Long-Term Debt	74	'	'	248
Line of Credit	507	'	'	104
Accounts Payable	30	'	'	26
Interest Payable	21	'	'	26
Wages Payable	22	'	'	29
Taxes Payable	16	'	'	9
Deferred Revenue	29	'	'	23
Other Current Liabilities	10	'	'	7
Total Current Liabilities	709	'	'	472
Long-Term Debt	1,815	'	'	1,815
Note Payable to Timberland Venture	783	'	'	783
Other Liabilities	94	'	'	91
Total Liabilities	3,401	'	'	3,161
Commitments and Contingencies	'	'	'	'
Stockholders' Equity	'	'	'	'
Preferred Stock, $0.01 Par Value, Authorized Shares - 75.0, Outstanding - None	0	'	'	0
Common Stock, $0.01 Par Value, Authorized Shares - 300.6, Outstanding (net of Treasury Stock) - 163.0 at September 30, 2013 and 162.0 at December 31, 2012	2	'	'	2
Additional Paid-In Capital	2,330	'	'	2,288
Retained Earnings (Accumulated Deficit)	-135	'	'	-97
Treasury Stock, at Cost, Common Shares - 27.0 at September 30, 2013 and 26.9 at December 31, 2012	-940	'	'	-938
Accumulated Other Comprehensive Income (Loss)	-27	-27	-29	-32
Total Stockholders' Equity	1,230	1,228	1,240	1,223
Total Liabilities and Stockholders' Equity	4,631	'	'	4,384
PLUM CREEK TIMBERLANDS L P [Member]	'	'	'	'
Current Assets:	'	'	'	'
Cash and Cash Equivalents	439	'	'	356
Accounts Receivable	35	'	'	22
Inventories	53	'	'	49
Deferred Tax Asset	8	'	'	7
Assets Held for Sale	38	'	'	61
Other Current Assets	17	'	'	13
Total Current Assets	590	'	'	508
Timber and Timberlands, net	3,395	'	'	3,363
Mineral Rights, net	242	'	'	87
Property, Plant and Equipment, net	118	'	'	127
Equity Investment in Timberland Venture	195	'	'	204
Deferred Tax Asset	19	'	'	19
Investment in Grantor Trusts (at Fair Value)	43	'	'	40
Other Assets	30	'	'	37
Total Assets	4,632	'	'	4,385
Current Liabilities:	'	'	'	'
Current Portion of Long-Term Debt	74	'	'	248
Line of Credit	507	'	'	104
Accounts Payable	30	'	'	26
Interest Payable	14	'	'	19
Wages Payable	22	'	'	29
Taxes Payable	16	'	'	9
Deferred Revenue	29	'	'	23
Other Current Liabilities	10	'	'	7
Total Current Liabilities	702	'	'	465
Long-Term Debt	1,815	'	'	1,815
Other Liabilities	95	'	'	92
Total Liabilities	2,612	'	'	2,372
Commitments and Contingencies	'	'	'	'
Stockholders' Equity	'	'	'	'
Accumulated Other Comprehensive Income (Loss)	-27	-27	-29	-32
PARTNERSHIP CAPITAL	'	'	'	'
Series T-1 Preferred Interest	790	'	'	790
Partners' Capital (Common Partnership Interests)	1,230	'	'	1,223
Total Partnership Capital	2,020	2,018	2,030	2,013
Total Liabilities and Partnership Capital	$4,632	'	'	$4,385

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets Parenthetical (Parentheticals) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, except Per Share data, unless otherwise specified
PLUM CREEK TIMBER CO INC [Member]	'	'
Preferred Stock, Par or Stated Value Per Share	$0.01	$0.01
Preferred Stock, Shares Authorized	75	75
Preferred Stock, Shares Outstanding	0	0
Common Stock, Par or Stated Value Per Share	$0.01	$0.01
Common Stock, Shares Authorized	300.6	300.6
Common Stock, Shares, Outstanding	163	162
Treasury Stock, Shares	27	26.9
PLUM CREEK TIMBERLANDS L P [Member]	'	'
Other Marketable Securities Noncurrent Fair Value	$42	$39

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
CASH FLOWS FROM OPERATING ACTIVITIES	'	'
Net Income	$174	$124
PLUM CREEK TIMBER CO INC [Member]	'	'
CASH FLOWS FROM OPERATING ACTIVITIES	'	'
Net Income	174	124
Adjustments to Reconcile Net Income to Net Cash Provided By Operating Activities:	'	'
Depreciation, Depletion and Amortization	86	87
Basis of Real Estate Sold	69	111
Equity Earnings from Timberland Venture	-47	-42
Distributions from Timberland Venture	56	56
Deferred Income Taxes	-1	-1
Deferred Revenue from Long-Term Gas Leases (Net of Amortization)	-6	-6
Timber Deed Acquired	-18	-98
Pension Contributions	0	-10
Working Capital Changes Impacting Cash Flow:	'	'
Working Capital Changes	-12	5
Other	19	11
Net Cash Provided By (Used In) Operating Activities	320	237
CASH FLOWS FROM INVESTING ACTIVITIES	'	'
Capital Expenditures (Excluding Timberland Acquisitions)	-51	-52
Timberlands Acquired	-80	-18
Mineral Rights Acquired	-156	0
Other	0	-1
Net Cash Provided By (Used In) Investing Activities	-287	-71
CASH FLOWS FROM FINANCING ACTIVITIES	'	'
Dividends	-212	-204
Borrowings on Line of Credit	1,251	1,712
Repayments on Line of Credit	-848	-1,709
Proceeds from Issuance of Long-term Debt	0	450
Debt Issuance Costs	0	-3
Principal Payments and Retirement of Long-Term Debt	-174	-350
Proceeds from Stock Options Exercises	35	5
Acquisition of Treasury Stock	-2	-1
Net Cash Provided By (Used In) Financing Activities	50	-100
Increase (Decrease) In Cash and Cash Equivalents	83	66
Cash and Cash Equivalents:	'	'
Beginning of Period	356	254
End of Period	439	320
PLUM CREEK TIMBERLANDS L P [Member]	'	'
CASH FLOWS FROM OPERATING ACTIVITIES	'	'
Net Income before Allocation to Series T-1 Preferred Interest and Partners	217	167
Net Income	174	124
Adjustments to Reconcile Net Income to Net Cash Provided By Operating Activities:	'	'
Depreciation, Depletion and Amortization	86	87
Basis of Real Estate Sold	69	111
Equity Earnings from Timberland Venture	-47	-42
Distributions from Timberland Venture	56	56
Deferred Income Taxes	-1	-1
Deferred Revenue from Long-Term Gas Leases (Net of Amortization)	-6	-6
Timber Deed Acquired	-18	-98
Pension Contributions	0	-10
Working Capital Changes Impacting Cash Flow:	'	'
Working Capital Changes	-12	5
Other	19	11
Net Cash Provided By (Used In) Operating Activities	363	280
CASH FLOWS FROM INVESTING ACTIVITIES	'	'
Capital Expenditures (Excluding Timberland Acquisitions)	-51	-52
Timberlands Acquired	-80	-18
Mineral Rights Acquired	-156	0
Other	0	-1
Net Cash Provided By (Used In) Investing Activities	-287	-71
CASH FLOWS FROM FINANCING ACTIVITIES	'	'
Cash Distributions to Common Partners	-179	-200
Cash Distributions for Series T-1 Preferred Interest	-43	-43
Borrowings on Line of Credit	1,251	1,712
Repayments on Line of Credit	-848	-1,709
Proceeds from Issuance of Long-term Debt	0	450
Debt Issuance Costs	0	-3
Principal Payments and Retirement of Long-Term Debt	-174	-350
Net Cash Provided By (Used In) Financing Activities	7	-143
Increase (Decrease) In Cash and Cash Equivalents	83	66
Cash and Cash Equivalents:	'	'
Beginning of Period	356	254
End of Period	$439	$320

Consolidated_Statements_of_Cas1

Consolidated Statements of Cash Flows Parenthetical (Parentheticals) (USD $)	3 Months Ended	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'	'
Loss from Catastrophes	$4	$4
PLUM CREEK TIMBERLANDS L P [Member]	'	'
Loss from Catastrophes	$4	$4

Basis_of_Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
Basis of Presentation	'
	Basis of Presentation
	General. When we refer to “Plum Creek,” “the company,” “we,” “us,” or “our,” we mean Plum Creek Timber Company, Inc., a Delaware Corporation and a real estate investment trust, or “REIT,” and all of its wholly-owned consolidated subsidiaries.
	The consolidated financial statements include all of the accounts of Plum Creek and its subsidiaries. At September 30, 2013, the company owned and managed approximately 6.3 million acres of timberlands in the Northwest, Southern, and Northeast United States, and owned 7 wood product conversion facilities in the Northwest United States. In April 2013, the company resumed limited operations of its previously idled lumber mill.  The facility was curtailed in June 2009 due to the sustained decline in lumber demand. Included in the 6.3 million acres are about 800,000 acres of higher value timberlands, which are expected to be sold and/or developed over the next fifteen years for recreational, conservation or residential purposes. Included within the 800,000 acres of higher value timberlands are approximately 600,000 acres we expect to sell for recreational uses, approximately 125,000 acres we expect to sell for conservation and approximately 75,000 acres that are identified as having development potential. In addition, the company has approximately 300,000 acres of non-strategic timberlands, which are expected to be sold in smaller acreage transactions over the near and medium term. In the meantime, all of our timberlands continue to be managed productively in our business of growing and selling timber.
	Plum Creek has elected to be taxed as a REIT under sections 856-860 of the United States Internal Revenue Code and, as such, generally does not pay corporate-level income tax. However, the company conducts certain non-REIT activities through various taxable REIT subsidiaries, which are subject to corporate-level income tax. These activities include our manufacturing operations, the harvesting and selling of logs, and the development and/or sales of some of our higher value timberlands. Plum Creek’s overall effective tax rate is lower than the federal statutory corporate rate due to Plum Creek’s status as a REIT.
	Intercompany transactions and accounts have been eliminated in consolidation. All transactions are denominated in United States dollars.
	The consolidated financial statements included in this Form 10-Q are unaudited and do not contain all of the information required by U.S. generally accepted accounting principles to be included in a full set of financial statements. The consolidated balance sheet at December 31, 2012 has been derived from the audited consolidated financial statements at that date but does not include all of the information and footnotes required by generally accepted accounting principles for complete financial statements. The audited financial statements in the company’s 2012 Annual Report on Form 10-K include a summary of significant accounting policies of the company and should be read in conjunction with this Form 10-Q. In the opinion of management, all material adjustments necessary to present fairly the results of operations for such periods have been included in this Form 10-Q. All such adjustments are of a normal and recurring nature. The results of operations for interim periods are not necessarily indicative of the results of operations for the entire year.
	New Accounting Pronouncements
	Presentation of Items Reclassified from Accumulated Other Comprehensive Income (AOCI). In 2013, the FASB issued new guidance requiring entities to disclose in a single location (either on the face of the income statement or in the footnotes) the effects of reclassifications out of AOCI. For items reclassified out of AOCI and into net income in their entirety, such as realized gains or losses on the company's available-for-sale securities, entities must disclose the effect of the reclassification on each affected net income item. For AOCI reclassification items not reclassified in their entirety into net income, such as amortization of the actuarial net loss on the company's defined benefit pension plans, entities must provide a cross reference to the notes in other disclosures that already provide information about those amounts. The new guidance is effective for annual reporting periods beginning after December 15, 2012, and interim periods within those years. The adoption did not have a material impact on the company's financial position, results of operations or cash flows. See Note 9 of the Notes to Consolidated Financial Statements.
PLUM CREEK TIMBERLANDS L P [Member]	'
Basis of Presentation	'
	Basis of Presentation
	General. Plum Creek Timberlands, L.P. is a Delaware Limited Partnership and a wholly-owned subsidiary of Plum Creek Timber Company, Inc. (“Parent”), a Delaware Corporation and a real estate investment trust, or “REIT.” References herein to “the Operating Partnership,” “we,” “us,” or “our” relate to Plum Creek Timberlands, L.P. and all of its wholly-owned consolidated subsidiaries; references to “Plum Creek” or “Parent” relate to Plum Creek Timber Company, Inc. and all of its wholly-owned consolidated subsidiaries.
	At September 30, 2013, the Operating Partnership owned and managed approximately 6.3 million acres of timberlands in the Northwest, Southern, and Northeast United States, and owned 7 wood product conversion facilities in the Northwest United States. In April 2013, the Operating Partnership resumed limited operations of its previously idled lumber mill.  The facility was curtailed in June 2009 due to the sustained decline in lumber demand. Included in the 6.3 million acres are about 800,000 acres of higher value timberlands, which are expected to be sold and/or developed over the next fifteen years for recreational, conservation or residential purposes. Included within the 800,000 acres of higher value timberlands are approximately 600,000 acres we expect to sell for recreational uses, approximately 125,000 acres we expect to sell for conservation and approximately 75,000 acres that are identified as having development potential. In addition, the Operating Partnership has approximately 300,000 acres of non-strategic timberlands, which are expected to be sold in smaller acreage transactions over the near and medium term. In the meantime, all of our timberlands continue to be managed productively in our business of growing and selling timber.
	The consolidated financial statements of the Operating Partnership include the accounts of Plum Creek Timberlands, L.P. and its subsidiaries. The Operating Partnership is 100% owned by Plum Creek. Plum Creek has no assets or liabilities other than its direct and indirect ownership interests in Plum Creek Timberlands, L.P. and its interest in Plum Creek Ventures I, LLC (“PC Ventures”), a 100% owned subsidiary of Plum Creek. The Parent has no operations other than its investment in these subsidiaries and transactions in its own equity, such as the issuance and/or repurchase of common stock and the receipt of proceeds from stock option exercises. Intercompany transactions and accounts between Plum Creek Timberlands, L.P. and its subsidiaries have been eliminated in consolidation. All transactions are denominated in United States dollars.
	Plum Creek Timber Company, Inc. has elected to be taxed as a REIT under sections 856-860 of the United States Internal Revenue Code and, as such, generally does not pay corporate-level income tax. However, the Operating Partnership conducts certain non-REIT activities through various wholly-owned taxable REIT subsidiaries, which are subject to corporate-level income tax. These activities include our manufacturing operations, the harvesting and selling of logs, and the development and/or sale of some of our higher value timberlands. The Operating Partnership’s tax provision includes the tax expense and/or benefit associated with Plum Creek’s taxable REIT subsidiaries, as well as any tax expense and/or benefit incurred by the REIT. The effective tax rate for the Operating Partnership is lower than the federal statutory corporate rate due to Plum Creek’s status as a REIT.
	The consolidated financial statements included in this Form 10-Q are unaudited and do not contain all of the information required by U.S. generally accepted accounting principles to be included in a full set of financial statements. These interim consolidated financial statements in this Form 10-Q should be read in conjunction with the audited consolidated financial statements of Plum Creek Timberlands, L.P. for the three years ended December 31, 2012, which were included on Form 10-K of Plum Creek Timber Company, Inc. and filed with the SEC on February 22, 2013, and which include a summary of significant accounting policies of the Operating Partnership. In the opinion of management, all material adjustments necessary to present fairly the results of operations for such periods have been included in this Form 10-Q. All such adjustments are of a normal and recurring nature. The results of operations for interim periods are not necessarily indicative of the results of operations for the entire year.
	New Accounting Pronouncements
	Presentation of Items Reclassified from Accumulated Other Comprehensive Income (AOCI). In 2013, the FASB issued new guidance requiring entities to disclose in a single location (either on the face of the income statement or in the footnotes) the effects of reclassifications out of AOCI. For items reclassified out of AOCI and into net income in their entirety, such as realized gains or losses on the Operating Partnership's available-for-sale securities, entities must disclose the effect of the reclassification on each affected net income item. For AOCI reclassification items not reclassified in their entirety into net income, such as amortization of the actuarial net loss on the Operating Partnership's defined benefit pension plans, entities must provide a cross reference to
	the notes in other disclosures that already provide information about those amounts. The new guidance is effective for annual reporting periods beginning after December 15, 2012, and interim periods within those years. The adoption did not have a material impact on the Operating Partnership's financial position, results of operations or cash flows. See Note 8 of the Notes to Consolidated Financial Statements.

Earnings_Per_Share

Earnings Per Share	9 Months Ended
	Sep. 30, 2013
Earnings Per Share [Abstract]	'
Earnings Per Share	'
	Earnings Per Share
	The following table sets forth the reconciliation of basic and diluted earnings per share for the quarterly and nine-month periods ended September 30 (in millions, except per share amounts):
		Quarter Ended September 30,
		2013			2012
	Net Income Available to Common Stockholders	$	72		$	59
	Denominator for Basic Earnings per Share	163			161.5
	Effect of Dilutive Securities – Stock Options	0.3			0.3
	Effect of Dilutive Securities – Restricted Stock Units and Value Management Plan	0.1			0.1
	Denominator for Diluted Earnings per Share – Adjusted for Dilutive Securities	163.4			161.9
	Per Share Amounts:
	Net Income Per Share – Basic	$	0.44		$	0.36
	Net Income Per Share – Diluted	$	0.44		$	0.36
		Nine Months Ended September 30,
		2013			2012
	Net Income Available to Common Stockholders	$	174		$	124
	Denominator for Basic Earnings per Share	162.7			161.5
	Effect of Dilutive Securities – Stock Options	0.4			0.3
	Effect of Dilutive Securities – Restricted Stock Units and Value Management Plan	0.1			—
	Denominator for Diluted Earnings per Share – Adjusted for Dilutive Securities	163.2			161.8
	Per Share Amounts:
	Net Income Per Share - Basic	$	1.06		$	0.77
	Net Income Per Share - Diluted	$	1.06		$	0.76
	Under the company's Stock Incentive Plan, the company grants restricted stock units, which prior to vesting, are entitled to non-forfeitable cash payments equal to dividends paid on the company's common shares. These awards are considered participating securities for purposes of computing basic and diluted earnings per share.
	Antidilutive options were excluded for certain periods from the computation of diluted earnings per share because the exercise prices of the options were greater than the average market price of the common shares. Antidilutive options were as follows for the quarterly and nine-month periods ended September 30 (shares in millions):
		Quarter Ended September 30,
		2013		2012
	Number of Options	—		1.1
	Range of Exercise Prices	N/A		$41.55 to $43.23
	Expiration on or before	N/A		Feb-21
		Nine Months Ended September 30,
		2013		2012
	Number of Options	—		1.1
	Range of Exercise Prices	N/A		$41.55 to $43.23
	Expiration on or before	N/A		Feb-21

Inventories

Inventories	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
Inventories	'
	Inventories
	Inventories, accounted for using the lower of average cost or market, consisted of the following (in millions):
		September 30, 2013		December 31, 2012
	Raw Materials (primarily logs)	$	8	$	9
	Work-In-Process	2		2
	Finished Goods	29		24
		39		35
	Supplies	14		14
	Total	$	53	$	49
PLUM CREEK TIMBERLANDS L P [Member]	'
Inventories	'
	Inventories
	Inventories, accounted for using the lower of average cost or market, consisted of the following (in millions):
		September 30, 2013		December 31, 2012
	Raw Materials (primarily logs)	$	8	$	9
	Work-In-Process	2		2
	Finished Goods	29		24
		39		35
	Supplies	14		14
	Total	$	53	$	49

Timber_and_Timberlands

Timber and Timberlands	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
Timber and Timberlands	'
	Timber and Timberlands
	Timber and Timberlands consisted of the following (in millions):
		September 30, 2013		December 31, 2012
	Timber and Logging Roads, net	$	2,162	$	2,169
	Timber Deeds, net	100		92
	Timberlands	1,133		1,102
	Timber and Timberlands, net	$	3,395	$	3,363
	In January 2012, the company purchased a timber deed in the Southern Resources Segment for $103 million, $5 million of which was paid as a deposit in December 2011. The timber deed encompassed approximately 4.7 million tons of standing timber and has an eight-year term. In March 2013, the company acquired, for $18 million, approximately 0.9 million tons of standing timber under a timber deed that expires in 2020.
	The volume acquired under a timber deed, along with future growth, is harvested over the term of the deed. The company reflects the purchase price of timber deeds in the Consolidated Statements of Cash Flows as outflows under Cash Provided by Operating Activities.
	During the third quarter of 2013, the company's Northern Resources Segment recognized a $4 million loss, representing the book basis of timber volume destroyed as a result of forest fires in Montana and Oregon.
PLUM CREEK TIMBERLANDS L P [Member]	'
Timber and Timberlands	'
	Timber and Timberlands
	Timber and Timberlands consisted of the following (in millions):
		September 30, 2013		December 31, 2012
	Timber and Logging Roads, net	$	2,162	$	2,169
	Timber Deeds, net	100		92
	Timberlands	1,133		1,102
	Timber and Timberlands, net	$	3,395	$	3,363
	In January 2012, the Operating Partnership purchased a timber deed in the Southern Resources Segment for $103 million, $5 million of which was paid as a deposit in December 2011. The timber deed encompassed approximately 4.7 million tons of standing timber and has an eight-year term. In March 2013, the Operating Partnership acquired, for $18 million, approximately 0.9 million tons of standing timber under a timber deed that expires in 2020.
	The volume acquired under a timber deed, along with future growth, is harvested over the term of the deed. The Operating Partnership reflects the purchase price of timber deeds in the Consolidated Statements of Cash Flows as outflows under Cash Provided by Operating Activities.
	During the third quarter of 2013, the Operating Partnership's Northern Resources Segment recognized a $4 million loss, representing the book basis of timber volume destroyed as a result of forest fires in Montana and Oregon.

Mineral_Rights_Mineral_Rights

Mineral Rights Mineral Rights	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
Intangible Assets Disclosure [Text Block]	'
	Mineral Rights
	In September 2013, the company acquired mineral rights in approximately 255 million tons of aggregate reserves at four quarries in Georgia for approximately $156 million.  The company is entitled to an overriding royalty in connection with the gross proceeds from the sale of crushed stone from these quarries.  Our mineral rights expire after 38 years.  The company estimates that annual depletion expense related to these mineral rights will be approximately $4 million a year for each of the next five years.
PLUM CREEK TIMBERLANDS L P [Member]	'
Intangible Assets Disclosure [Text Block]	'
	Mineral Rights
	In September 2013, the Operating Partnership acquired mineral rights in approximately 255 million tons of aggregate reserves at four quarries in Georgia for approximately $156 million.  The Operating Partnership is entitled to an overriding royalty in connection with the gross proceeds from the sale of crushed stone from these quarries.  Our mineral rights expire after 38 years.  The Operating Partnership estimates that annual depletion expense related to these mineral rights will be approximately $4 million a year for each of the next five years.

Property_Plant_and_Equipment

Property, Plant and Equipment	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
Property, Plant and Equipment	'
	Property, Plant and Equipment
	Property, Plant and Equipment consisted of the following (in millions):
		September 30, 2013			December 31, 2012
	Land, Buildings and Improvements	$	88		$	88
	Machinery and Equipment	326			318
		414			406
	Accumulated Depreciation	(296		)	(279		)
	Property, Plant and Equipment, net	$	118		$	127
PLUM CREEK TIMBERLANDS L P [Member]	'
Property, Plant and Equipment	'
	Property, Plant and Equipment
	Property, Plant and Equipment consisted of the following (in millions):
		September 30, 2013			December 31, 2012
	Land, Buildings and Improvements	$	88		$	88
	Machinery and Equipment	326			318
		414			406
	Accumulated Depreciation	(296		)	(279		)
	Property, Plant and Equipment, net	$	118		$	127

Income_Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
Income Tax Disclosure [Text Block]	'
	Income Taxes
	Plum Creek has elected to be taxed as a REIT under sections 856-860 of the United States Internal Revenue Code. A REIT generally does not pay corporate-level income tax if it distributes 100% of its taxable income to shareholders and satisfies other organizational and operational requirements as set forth in the Internal Revenue Code. If a company fails to qualify as a REIT in any taxable year, it will be subject to federal income taxes at regular corporate rates (including any applicable alternative minimum tax) and may not be able to qualify as a REIT for four subsequent taxable years.
	Plum Creek operates as a REIT through various wholly-owned subsidiaries and a joint venture partnership. The activities of the operating partnerships and joint venture partnership consist primarily of sales of standing timber under pay-as-cut sales contracts.
	Plum Creek conducts certain activities through various wholly-owned taxable REIT subsidiaries, which are subject to corporate-level income tax. These activities include the company's manufacturing operations, the harvesting and sale of logs, and the development and/or sale of some of the company's higher and better use timberlands. Plum Creek's wholly-owned taxable REIT subsidiaries file a consolidated federal income tax return.
	Prior to 2011, Plum Creek was generally subject to corporate-level tax (built-in gains tax) when the company made a taxable disposition of certain properties acquired in a 2001 merger. The built-in gains tax applied to gains recognized from such asset sales to the extent that the fair value of the property exceeded its tax basis at the merger date. Built-in gains tax was generally not payable on dispositions of property to the extent the proceeds from such dispositions were reinvested in qualifying like-kind replacement property.
	The company's 2008 federal income tax return is currently being audited by the Internal Revenue Service (“IRS”). The IRS has proposed an adjustment to the company's U.S. federal income tax treatment of the Timberland Venture formation transaction, which occurred on October 1, 2008, on the basis that the transfer of the timberlands to Southern Diversified Timber, LLC was a taxable transaction to the company at the time of the transfer rather than a nontaxable capital contribution to the Timberland Venture. We will file a protest with IRS Appeals.
	If the IRS's position were upheld on administrative or judicial appeal, it could result in a maximum built-in gains tax liability of approximately $100 million. In addition, the company could be required to accelerate the distribution to its stockholders of up to $600 million of gain from the transaction. The company expects that as much as 80% of any such distribution could be made with the company's common stock, and stockholders would be subject to tax on the distribution at the applicable capital gains tax rate. The company would also be required to pay interest, which could be substantial, and, if applicable, penalties.
	We believe the transfer of the timberlands was a nontaxable contribution to the Timberland Venture and not a taxable transaction. We have not accrued income taxes for financial reporting purposes with respect to this matter and do not believe it is reasonably possible any material accrual will be made within the next twelve months. We are confident in our position and believe that the proposed re-characterization of the Timberland Venture formation transaction by the IRS will ultimately be unsuccessful. We intend to vigorously contest this re-characterization.
PLUM CREEK TIMBERLANDS L P [Member]	'
Income Tax Disclosure [Text Block]	'
	Income Taxes
	Plum Creek Timberlands, L.P. is a wholly-owned limited partnership and therefore, not subject to income tax. Plum Creek Timberlands, L.P.’s taxable income is allocated 100% (directly and indirectly) to its parent, Plum Creek Timber Company, Inc., which has elected to be taxed as a REIT under sections 856-860 of the United States Internal Revenue Code. A REIT generally does not pay corporate-level income tax if it distributes 100% of its taxable income to shareholders and satisfies other organizational and operational requirements as set forth in the Internal Revenue Code. If a company fails to qualify as a REIT in any taxable year, it will be subject to federal income taxes at regular corporate rates (including any applicable alternative minimum tax) and may not be able to qualify as a REIT for four subsequent taxable years.
	Plum Creek operates as a REIT through various wholly-owned subsidiaries and a joint venture partnership. The activities of the operating partnerships and joint venture partnership consist primarily of sales of standing timber under pay-as-cut sales contracts.
	Plum Creek conducts certain activities through various wholly-owned taxable REIT subsidiaries, which are subject to corporate-level income tax. These activities include the company's manufacturing operations, the harvesting and sale of logs, and the development and/or sale of some of the company's higher and better use timberlands. Plum Creek's wholly-owned taxable REIT subsidiaries file a consolidated federal income tax return.
	Prior to 2011, Plum Creek was generally subject to corporate-level tax (built-in gains tax) when the company made a taxable disposition of certain properties acquired in a 2001 merger. The built-in gains tax applied to gains recognized from such asset sales to the extent that the fair value of the property exceeded its tax basis at the merger date. Built-in gains tax was generally not payable on dispositions of property to the extent the proceeds from such dispositions were reinvested in qualifying like-kind replacement property.
	Plum Creek's 2008 federal income tax return is currently being audited by the Internal Revenue Service (“IRS”). The IRS has proposed an adjustment to Plum Creek's U.S. federal income tax treatment of the Timberland Venture formation transaction, which occurred on October 1, 2008, on the basis that the transfer of the timberlands to Southern Diversified Timber, LLC was a taxable transaction to Plum Creek at the time of the transfer rather than a nontaxable capital contribution to the Timberland Venture. Plum Creek will file a protest with IRS Appeals.
	If the IRS's position were upheld on administrative or judicial appeal, it could result in a maximum built-in gains tax liability of approximately $100 million. In addition, Plum Creek could be required to accelerate the distribution to its stockholders of up to $600 million of gain from the transaction. Plum Creek expects that as much as 80% of any such distribution could be made with Plum Creek's common stock, and stockholders would be subject to tax on the distribution at the applicable capital gains tax rate. Plum Creek would also be required to pay interest, which could be substantial, and, if applicable, penalties.
	We believe the transfer of the timberlands was a nontaxable contribution to the Timberland Venture and not a taxable transaction. We have not accrued income taxes for financial reporting purposes with respect to this matter and do not believe it is reasonably possible any material accrual will be made within the next twelve months. We are confident in our position and believe that the proposed re-characterization of the Timberland Venture formation transaction by the IRS will ultimately be unsuccessful. We intend to vigorously contest this re-characterization.

Borrowings

Borrowings	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
Borrowings	'
	Borrowings
	Debt consisted of the following (in millions):
		September 30, 2013		December 31, 2012
	Variable Rate Debt
	Term Credit Agreement (A)	$	450	$	450
	Revolving Line of Credit (B)	507		104
	Fixed Rate Debt
	Senior Notes	1,439		1,613
	Note Payable to Timberland Venture	783		783
	Total Debt	3,179		2,950
	Less:
	Current Portion of Long-Term Debt	74		248
	Line of Credit	507		104
	Long-Term Portion	$	2,598	$	2,598
	(A)	The company has a $450 million term credit agreement that matures on April 3, 2019. The interest rate on the $450 million term credit agreement was 1.68% and 1.71% as of September 30, 2013 and December 31, 2012, respectively. After giving effect to expected patronage distributions, the effective net interest rate on the term loan was approximately 1% as of both September 30, 2013 and December 31, 2012. On November 4, 2013, the company repaid $225 million of borrowings outstanding under the term credit agreement. See Note 16 of the Notes to Consolidated Financial Statements.
	(B)	The weighted-average interest rate for the borrowings on the line of credit was 1.38% and 1.43% as of September 30, 2013 and December 31, 2012, respectively. As of September 30, 2013, we had $507 million of borrowings and $1 million of standby letters of credit outstanding; $192 million remained available for borrowing under our $700 million line of credit. As of October 1, 2013, $355 million of the borrowings outstanding under our line of credit was repaid.
PLUM CREEK TIMBERLANDS L P [Member]	'
Borrowings	'
	Borrowings
	Debt consisted of the following (in millions):
		September 30, 2013		December 31, 2012
	Variable Rate Debt
	Term Credit Agreement (A)	$	450	$	450
	Revolving Line of Credit (B)	507		104
	Fixed Rate Debt
	Senior Notes	1,439		1,613
	Total Debt	2,396		2,167
	Less:
	Current Portion of Long-Term Debt	74		248
	Line of Credit	507		104
	Long-Term Portion	$	1,815	$	1,815
	(A)	The Operating Partnership has a $450 million term credit agreement that matures on April 3, 2019. The interest rate on the $450 million term credit agreement was 1.68% and 1.71% as of September 30, 2013 and December 31, 2012, respectively. After giving effect to expected patronage distributions, the effective net interest rate on the term loan was approximately 1% as of both September 30, 2013 and December 31, 2012. On November 4, 2013, the Operating Partnership repaid $225 million of borrowings outstanding under the term credit agreement. See Note 15 of the Notes to Consolidated Financial Statements.
	(B)	The weighted-average interest rate for the borrowings on the line of credit was 1.38% and 1.43% as of September 30, 2013 and December 31, 2012, respectively. As of September 30, 2013, we had $507 million of borrowings and $1 million of standby letters of credit outstanding; $192 million remained available for borrowing under our $700 million line of credit. As of October 1, 2013, $355 million of the borrowings outstanding under our line of credit was repaid.

Stockholders_Equity

Stockholders' Equity (PLUM CREEK TIMBER CO INC [Member])	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
Stockholders' Equity	'
	Stockholders’ Equity
	The changes in the company’s stockholders’ equity accounts were as follows during 2013 (in millions):
		Common Stock											Retained						Accumulated
													Earnings (Accumulated Deficit)						Other
																			Comprehensive
		Shares			Dollars				Paid-in							Treasury			Income (Loss)			Total
									Capital							Stock						Equity
	January 1, 2013	162			$	2			$	2,288			$	(97	)	$	(938	)	$	(32	)	$	1,223
	Net Income												56									56
	Other Comprehensive Income (Loss)																		3			3
	Dividends												(68		)							(68		)
	Stock Option Exercises	0.6			—				25													25
	Shares Issued under Stock Incentive Plans	0.1			—				—													—
	Share-based Compensation								3													3
	Common Stock Repurchased	—			—											(2		)				(2		)
	March 31, 2013	162.7			$	2			$	2,316			$	(109	)	$	(940	)	$	(29	)	$	1,240
	Net Income												46									46
	Other Comprehensive Income (Loss)																		2			2
	Dividends												(72		)							(72		)
	Stock Option Exercises	0.3			—				10													10
	Share-based Compensation								2													2
	June 30, 2013	163			$	2			$	2,328			$	(135	)	$	(940	)	$	(27	)	$	1,228
	Net Income												72									72
	Other Comprehensive Income (Loss)																		—			—
	Dividends												(72		)							(72		)
	Share-based Compensation								2													2
	September 30, 2013	163			$	2			$	2,330			$	(135	)	$	(940	)	$	(27	)	$	1,230
	The changes in the company’s accumulated other comprehensive income by component, net of tax, were as follows during 2013 (in millions):
		Net Unrealized Holding Gains (Losses)				Defined Benefit Plan Actuarial Net Loss				Total
	January 1, 2013	$	8			$	(40	)		$	(32	)
	Other Comprehensive Income (Loss) before Reclassifications	2				—				2
	Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	—				1				1
	31-Mar-13	$	10			$	(39	)		$	(29	)
	Other Comprehensive Income (Loss) before Reclassifications	1				—				1
	Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	—				1				1
	30-Jun-13	$	11			$	(38	)		$	(27	)
	Other Comprehensive Income (Loss) before Reclassifications	(1		)		—				(1		)
	Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	—				1				1
	30-Sep-13	$	10			$	(37	)		$	(27	)
	Summarized below are the reclassifications out of accumulated other comprehensive income for the quarter ended September 30, 2013 (in millions):
	Details about Accumulated Other Comprehensive Income Components	Amount Reclassified from Accumulated Other Comprehensive Income				Affected Line Items in the Statement Where Net Income is Presented
	Amortization of Actuarial Loss	$	1			See Note 11 - Employee Pension Plans
	Total	$	1
	Summarized below are the reclassifications out of accumulated other comprehensive income for the nine months ended September 30, 2013 (in millions):
	Details about Accumulated Other Comprehensive Income Components	Amount Reclassified from Accumulated Other Comprehensive Income				Affected Line Items in the Statement Where Net Income is Presented
	Amortization of Actuarial Loss	$	3			See Note 11 - Employee Pension Plans
	Total	$	3

Partners_Capital

Partners' Capital (PLUM CREEK TIMBERLANDS L P [Member])	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBERLANDS L P [Member]	'
Partners' Capital	'
	Partners’ Capital
	The changes in the Operating Partnership’s capital accounts were as follows during 2013 (in millions):
		Preferred			Common			Accumulated			Total
		Partnership			Partners’			Other			Partnership
		Interest			Capital			Comprehensive			Capital
								Income (Loss)
	January 1, 2013	$	790		$	1,255		$	(32	)	$	2,013
	Net Income before Allocation to Series T-1 Preferred Interest and Partners				70						70
	Other Comprehensive Income (Loss)							3			3
	Net Income Allocation to Series T-1 Preferred Interest	14			(14		)				—
	Distributions to Partners (Common Partnership Interests)				(45		)				(45		)
	Distributions for Series T-1 Preferred Interest	(14		)							(14		)
	Capital Contributions from Parent				3						3
	March 31, 2013	$	790		$	1,269		$	(29	)	$	2,030
	Net Income before Allocation to Series T-1 Preferred Interest and Partners				61						61
	Other Comprehensive Income (Loss)							2			2
	Net Income Allocation to Series T-1 Preferred Interest	15			(15		)				—
	Distributions to Partners (Common Partnership Interests)				(62		)				(62		)
	Distributions for Series T-1 Preferred Interest	(15		)							(15		)
	Capital Contributions from Parent				2						2
	June 30, 2013	$	790		$	1,255		$	(27	)	$	2,018
	Net Income before Allocation to Series T-1 Preferred Interest and Partners				86						86
	Other Comprehensive Income (Loss)							—			—
	Net Income Allocation to Series T-1 Preferred Interest	14			(14		)				—
	Distributions to Partners (Common Partnership Interests)				(72		)				(72		)
	Distributions for Series T-1 Preferred Interest	(14		)							(14		)
	Capital Contributions from Parent				2						2
	September 30, 2013	$	790		$	1,257		$	(27	)	$	2,020
	The changes in the Operating Partnership's accumulated other comprehensive income by component, net of tax, were as follows during 2013 (in millions):
		Net Unrealized Holding Gains (Losses)			Defined Benefit Plan Actuarial Net Loss			Total
	January 1, 2013	$	8		$	(40	)	$	(32	)
	Other Comprehensive Income (Loss) before Reclassifications	2			—			2
	Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	—			1			1
	31-Mar-13	$	10		$	(39	)	$	(29	)
	Other Comprehensive Income (Loss) before Reclassifications	1			—			1
	Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	—			1			1
	30-Jun-13	$	11		$	(38	)	$	(27	)
	Other Comprehensive Income (Loss) before Reclassifications	(1		)	—			(1		)
	Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	—			1			1
	30-Sep-13	$	10		$	(37	)	$	(27	)
	Summarized below are the reclassifications out of accumulated other comprehensive income for the quarter ended September 30, 2013 (in millions):
	Details about Accumulated Other Comprehensive Income Components	Amount Reclassified from Accumulated Other Comprehensive Income			Affected Line Items in the Statement Where Net Income is Presented
	Amortization of Actuarial Loss	$	1		See Note 10 - Employee Pension Plans
	Total	$	1
	Summarized below are the reclassifications out of accumulated other comprehensive income for the nine months ended September 30, 2013 (in millions):
	Details about Accumulated Other Comprehensive Income Components	Amount Reclassified from Accumulated Other Comprehensive Income			Affected Line Items in the Statement Where Net Income is Presented
	Amortization of Actuarial Loss	3			See Note 10 - Employee Pension Plans
	Total	$	3

Fair_Value_Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
Fair Value Measurements	'
	Fair Value Measurements
	Assets and Liabilities Measured at Fair Value on a Recurring Basis. The company’s fair value measurements of its cash equivalents, available-for-sale securities, and trading securities, measured on a recurring basis, are categorized as Level 1 measurements under the fair value hierarchy in the Accounting Standards Codification. A Level 1 valuation is based on quoted prices in active markets at the measurement date for identical unrestricted assets or liabilities. Summarized below are the Level 1 assets reported in the company’s financial statements at fair value, measured on a recurring basis (in millions):
		Balance at			Fair Value Measurements
		30-Sep-13			at Reporting Date Using
					Quoted Prices in Active
					Markets of Identical Assets
					(Level 1 Measurements)
	Cash Equivalents (A)	$	434		$	434
	Available-for-Sale Securities (B)	37			37
	Trading Securities (B)	5			5
	Total	$	476		$	476
		Balance at			Fair Value Measurements
		31-Dec-12			at Reporting Date Using
					Quoted Prices in Active
					Markets of Identical Assets
					(Level 1 Measurements)
	Cash Equivalents (A)	$	354		$	354
	Available-for-Sale Securities (B)	34			34
	Trading Securities (B)	5			5
	Total	$	393		$	393
	(A)	Consists of several money market funds and is included in the $439 million and $356 million of Cash and Cash Equivalents in the Consolidated Balance Sheets at September 30, 2013 and December 31, 2012, respectively.
	(B)	Consists of several mutual funds and is included in Investment in Grantor Trusts in the Consolidated Balance Sheets at September 30, 2013 and December 31, 2012. At September 30, 2013, investments in these mutual funds were approximately 45% in domestic (U.S.) equities, 25% in international equities and 30% in debt securities.
	Available-for-Sale Securities. Certain investments in the grantor trusts relate to the company's non-qualified pension plans and are classified as available-for-sale securities. The company has invested in various money market, debt and equity mutual funds and plans to use these investments to fund its non-qualified pension obligations. Unrealized holding gains and losses are included as a component of accumulated other comprehensive income. The company records changes in unrealized holding gains and losses in Other Comprehensive Income, unless an other than temporary impairment has occurred, which is then charged to expense. Changes in the fair value of available-for-sale securities were not material to the company's financial position or results of operations. See Note 9 of the Notes to Consolidated Financial Statements.
	Trading Securities. Certain investments in the grantor trusts relate to the company's deferred compensation plans and are classified as trading securities. Deferred compensation amounts are invested in various money market, debt and equity mutual funds. The company plans to use these investments to fund deferred compensation obligations. Realized gains and losses and changes in unrealized gains and losses (and a corresponding amount of compensation expense) are recognized in the company's Consolidated Statements of Income. Deferred compensation obligations are included in Other Liabilities and were $5 million at both September 30, 2013 and December 31, 2012. Changes in the fair value of trading securities were not material to the company's financial position or results of operations.
	Other Instruments. The carrying amount of notes receivable approximates fair value due to the short-term maturities of these instruments. Summarized below are the carrying amount and fair value of the company's debt (estimated using the discounted cash flows method) along with the categorization under the fair value hierarchy in the Accounting Standards Codification (in millions):
						Fair Value at September 30, 2013
			Carrying Amount at September 30, 2013			Quoted Prices		Significant		Significant		Total
						In Active		Observable		Unobservable
						Markets for		Inputs		Inputs
						Identical Assets		(Level 2)		(Level 3)
						(Level 1)
	Public Debt (A)		$	1,353		$	—	$	1,387	$	—	$	1,387
	Private Debt (B)		86			—		88		—		88
	Term Credit Agreement (C)		450			—		450		—		450
	Line of Credit (D)		507			—		507		—		507
	Note Payable to Timberland Venture (E)		783			—		—		926		926
	Total Debt		$	3,179		$	—	$	2,432	$	926	$	3,358
						Fair Value at December 31, 2012
			Carrying Amount at			Quoted Prices		Significant		Significant		Total
			31-Dec-12			In Active		Observable		Unobservable
						Markets for		Inputs		Inputs
						Identical Assets		(Level 2)		(Level 3)
						(Level 1)
	Public Debt (A)		$	1,353		$	—	$	1,465	$	—	$	1,465
	Private Debt (B)		260			—		266		—		266
	Term Credit Agreement (C)		450			—		450		—		450
	Line of Credit (D)		104			—		104		—		104
	Note Payable to Timberland Venture (E)		783			—		—		973		973
	Total Debt		$	2,950		$	—	$	2,285	$	973	$	3,258
	(A)	Fair value of the company's Public Debt (publicly issued Senior Notes) is estimated using multiple market quotes for the company's public bonds.
	(B)	Fair value of the company's Private Debt (Senior Notes with various maturities and fixed interest rates which are privately placed with various lenders) is estimated using market quotes for the company's Public Debt adjusted for the different maturities and an illiquidity premium.
	(C)	Fair value is estimated by adjusting the spread over LIBOR to a current market quote for comparable debt.
	(D)	Fair value is estimated by adjusting the spread over LIBOR to a current market quote for comparable credit lines.
	(E)	Fair value is estimated by using market quotes for the company's Public Debt adjusted by an estimated risk premium for holding company debt and the different maturity.
	Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis. There were no fair value measurements of assets or liabilities measured on a nonrecurring basis during the nine-month periods ended September 30, 2013 and 2012.
PLUM CREEK TIMBERLANDS L P [Member]	'
Fair Value Measurements	'
	Fair Value Measurements
	Assets and Liabilities Measured at Fair Value on a Recurring Basis. The Operating Partnership’s fair value measurements of its cash equivalents, available-for-sale securities, and trading securities, measured on a recurring basis, are categorized as Level 1 measurements under the fair value hierarchy in the Accounting Standards Codification. A Level 1 valuation is based on quoted prices in active markets at the measurement date for identical unrestricted assets or liabilities. Summarized below are the Level 1 assets reported in the Operating Partnership’s financial statements at fair value, measured on a recurring basis (in millions):
		Balance at			Fair Value Measurements
		30-Sep-13			at Reporting Date Using
					Quoted Prices in Active
					Markets of Identical Assets
					(Level 1 Measurements)
	Cash Equivalents (A)	$	434		$	434
	Available-for-Sale Securities (B)	37			37
	Trading Securities (B)	5			5
	Total	$	476		$	476
		Balance at			Fair Value Measurements
		31-Dec-12			at Reporting Date Using
					Quoted Prices in Active
					Markets of Identical Assets
					(Level 1 Measurements)
	Cash Equivalents (A)	$	354		$	354
	Available-for-Sale Securities (B)	34			34
	Trading Securities (B)	5			5
	Total	$	393		$	393
	(A)	Consists of several money market funds and is included in the $439 million and $356 million of Cash and Cash Equivalents in the Consolidated Balance Sheets at September 30, 2013 and December 31, 2012, respectively.
	(B)	Consists of several mutual funds and is included in Investment in Grantor Trusts in the Consolidated Balance Sheets at September 30, 2013 and December 31, 2012. At September 30, 2013, investments in these mutual funds were approximately 45% in domestic (U.S.) equities, 25% in international equities and 30% in debt securities.
	Available-for-Sale Securities. Certain investments in the grantor trusts relate to the Operating Partnership's non-qualified pension plans and are classified as available-for-sale securities. The Operating Partnership has invested in various money market, debt and equity mutual funds and plans to use these investments to fund its non-qualified pension obligations. Unrealized holding gains and losses are included as a component of accumulated other comprehensive income. The Operating Partnership records changes in unrealized holding gains and losses in Other Comprehensive Income, unless an other than temporary impairment has occurred, which is then charged to expense. Changes in the fair value of available-for-sale securities were not material to the Operating Partnership's financial position or results of operations. See Note 8 of the Notes to Consolidated Financial Statements.
	Trading Securities. Certain investments in the grantor trusts relate to the Operating Partnership's deferred compensation plans and are classified as trading securities. Deferred compensation amounts are invested in various money market, debt and equity mutual funds. The Operating Partnership plans to use these investments to fund deferred compensation obligations. Realized gains and losses and changes in unrealized gains and losses (and a corresponding amount of compensation expense) are recognized in the Operating Partnership's Consolidated Statements of Income. Deferred compensation obligations are included in Other Liabilities and were $5 million at both September 30, 2013 and December 31, 2012. Changes in the fair value of trading securities were not material to the Operating Partnership's financial position or results of operations.
	Other Instruments. The carrying amount of notes receivable approximates fair value due to the short-term maturities of these instruments. Summarized below are the carrying amount and fair value of the Operating Partnership's debt (estimated using the discounted cash flows method) along with the categorization under the fair value hierarchy in the Accounting Standards Codification (in millions):
						Fair Value at September 30, 2013
			Carrying Amount at September 30, 2013			Quoted Prices		Significant		Significant		Total
						In Active		Observable		Unobservable
						Markets for		Inputs		Inputs
						Identical Assets		(Level 2)		(Level 3)
						(Level 1)
	Public Debt (A)		$	1,353		$	—	$	1,387	$	—	$	1,387
	Private Debt (B)		86			—		88		—		88
	Term Credit Agreement (C)		450			—		450		—		450
	Line of Credit (D)		507			—		507		—		507
	Total Debt		$	2,396		$	—	$	2,432	$	—	$	2,432
						Fair Value at December 31, 2012
			Carrying Amount at			Quoted Prices		Significant		Significant		Total
			31-Dec-12			In Active		Observable		Unobservable
						Markets for		Inputs		Inputs
						Identical Assets		(Level 2)		(Level 3)
						(Level 1)
	Public Debt (A)		$	1,353		$	—	$	1,465	$	—	$	1,465
	Private Debt (B)		260			—		266		—		266
	Term Credit Agreement (C)		450			—		450		—		450
	Line of Credit (D)		104			—		104		—		104
	Total Debt		$	2,167		$	—	$	2,285	$	—	$	2,285
	(A)	Fair value of the Operating Partnership's Public Debt (publicly issued Senior Notes) is estimated using multiple market quotes for the Operating Partnership's public bonds.
	(B)	Fair value of the Operating Partnership's Private Debt (Senior Notes with various maturities and fixed interest rates which are privately placed with various lenders) is estimated using market quotes for the Operating Partnership's Public Debt adjusted for the different maturities and an illiquidity premium.
	(C)	Fair value is estimated by adjusting the spread over LIBOR to a current market quote for comparable debt.
	(D)	Fair value is estimated by adjusting the spread over LIBOR to a current market quote for comparable credit lines.
	Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis. There were no fair value measurements of assets or liabilities measured on a nonrecurring basis during the nine-month periods ended September 30, 2013 and 2012.

Employee_Pension_Plans

Employee Pension Plans	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
Employee Pension Plans	'
	Employee Pension Plans
	The components of pension cost were as follows for the quarterly and nine-month periods ended September 30 (in millions):
		Quarter Ended September 30,
		2013			2012
	Service Cost	$	2		$	2
	Interest Cost	2			2
	Expected Return on Plan Assets	(2		)	(2		)
	Recognized Actuarial Loss	1			1
	Total Pension Cost	$	3		$	3
		Nine Months Ended September 30,
		2013			2012
	Service Cost	$	6		$	6
	Interest Cost	6			6
	Expected Return on Plan Assets	(6		)	(6		)
	Recognized Actuarial Loss	3			3
	Total Pension Cost	$	9		$	9
	It is the company’s policy to fund its qualified plan annually such that the fair value of plan assets equals or exceeds the actuarially computed accumulated benefit obligation (the approximate actuarially computed current pension obligation if the plan were discontinued) over a market cycle (generally 3 to 5 years). During the first nine months of 2013, the company has not made any contributions to its qualified or non-qualified pension plans. Depending on asset returns and interest rates, the company may contribute between $0 and $10 million to the qualified plan during the fourth quarter of 2013. The company expects to contribute between $0 and $2 million to its grantor trust associated with its non-qualified pension plans during the fourth quarter of 2013.
PLUM CREEK TIMBERLANDS L P [Member]	'
Employee Pension Plans	'
	Employee Pension Plans
	The components of pension cost were as follows for the quarterly and nine-month periods ended September 30 (in millions):
		Quarter Ended September 30,
		2013			2012
	Service Cost	$	2		$	2
	Interest Cost	2			2
	Expected Return on Plan Assets	(2		)	(2		)
	Recognized Actuarial Loss	1			1
	Total Pension Cost	$	3		$	3
		Nine Months Ended September 30,
		2013			2012
	Service Cost	$	6		$	6
	Interest Cost	6			6
	Expected Return on Plan Assets	(6		)	(6		)
	Recognized Actuarial Loss	3			3
	Total Pension Cost	$	9		$	9
	It is the Operating Partnership’s policy to fund its qualified plan annually such that the fair value of plan assets equals or exceeds the actuarially computed accumulated benefit obligation (the approximate actuarially computed current pension obligation if the plan were discontinued) over a market cycle (generally 3 to 5 years). During the first nine months of 2013, the Operating Partnership has not made any contributions to its qualified or non-qualified pension plans. Depending on asset returns and interest rates, the Operating Partnership may contribute between $0 and $10 million to the qualified plan during the fourth quarter of 2013. The Operating Partnership expects to contribute between $0 and $2 million to its grantor trust associated with its non-qualified pension plans during the fourth quarter of 2013.

Commitments_and_Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
Commitments and Contingencies	'
	Commitments and Contingencies
	Contingencies. The company is subject to regulations regarding forest, harvest and manufacturing practices and is, from time to time, involved in various legal proceedings, including, but not limited to, environmental and regulatory matters, incidental to its business. Reserves have been established for any probable losses. Except as discussed elsewhere, management does not believe that these matters, individually or in the aggregate, are material. However, it is possible that one or more of these matters could become material in the future, and an unfavorable outcome in one or more of these matters could have a material negative financial impact on the company. See also Note 7 of the Notes to Consolidated Financial Statements for a discussion of a tax proceeding involving the company and its consolidated subsidiaries.
PLUM CREEK TIMBERLANDS L P [Member]	'
Commitments and Contingencies	'
	Commitments and Contingencies
	Contingencies. The Operating Partnership is subject to regulations regarding forest, harvest and manufacturing practices and is, from time to time, involved in various legal proceedings, including, but not limited to, environmental and regulatory matters, incidental to its business. Reserves have been established for any probable losses. Except as discussed elsewhere, management does not believe that these matters, individually or in the aggregate, are material. However, it is possible that one or more of these matters could become material in the future, and an unfavorable outcome in one or more of these matters could have a material negative financial impact on the Operating Partnership. See also Note 6 of the Notes to Consolidated Financial Statements for a discussion of a tax proceeding involving Plum Creek.

Variable_Interest_Entities

Variable Interest Entities	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
Consolidation, Variable Interest Entity, Policy [Policy Text Block]	'
	Variable Interest Entities
	In 2008, the company contributed 454,000 acres of timberlands located in its Southern Resources Segment to Southern Diversified Timber, LLC (“the Timberland Venture”) in exchange for a $705 million preferred interest and a 9% common interest valued at $78 million. The Timberland Venture’s other member, an affiliate of The Campbell Group LLC, contributed $783 million of cash in exchange for 91% of the Timberland Venture’s common interest. Following the contribution, the company borrowed $783 million from the Timberland Venture (“Note Payable to Timberland Venture”). The company accounts for its interest in the Timberland Venture under the equity method of accounting.
	The Timberland Venture is a variable interest entity. The primary operating activities of the Timberland Venture consist of owning timberlands and entering into cutting contracts with an affiliate of the other member. Besides quarterly interest payments on the Note Payable to Timberland Venture, the company has not provided financing or other support to the venture. The venture generates sufficient cash from operating activities to finance its operations.
	We are not the primary beneficiary of the Timberland Venture. The company does not manage the day-to-day operations of the Timberland Venture, it has only limited protective rights and its involvement is generally limited to receiving distributions on its preferred and common interests. We are not the primary beneficiary because we do not direct the activities that most significantly impact the Timberland Venture’s economic performance. We believe that the activities that most significantly impact the Timberland Venture’s economic performance include managing the timberlands along with the timing and extent of the harvesting activities, neither of which we control.
	The carrying amount of the investment is $195 million at September 30, 2013 and $204 million at December 31, 2012, and it is reported in the Consolidated Balance Sheets as Equity Investment in Timberland Venture. Our maximum exposure to loss is $195 million, the carrying amount of the investment. Generally, losses are first allocated among the common interests based on positive capital accounts in which we hold a 9% common interest. No losses are allocated to our preferred interest ($705 million) until the common interests have absorbed losses of approximately $861 million.
PLUM CREEK TIMBERLANDS L P [Member]	'
Consolidation, Variable Interest Entity, Policy [Policy Text Block]	'
	Variable Interest Entities
	In 2008, a subsidiary of the Operating Partnership, Plum Creek Timber Operations I, LLC (“PC Member”), contributed 454,000 acres of timberlands located in its Southern Resources Segment to Southern Diversified Timber, LLC (“the Timberland Venture”) in exchange for a $705 million preferred interest and a 9% common interest valued at $78 million. The Timberland Venture’s other member, an affiliate of The Campbell Group LLC, contributed $783 million of cash in exchange for 91% of the Timberland Venture’s common interest. Following the formation of the Timberland Venture, Plum Creek Ventures I, LLC (“PC Ventures”), a 100% wholly-owned subsidiary of Plum Creek Timber Company, Inc., borrowed $783 million from the Timberland Venture. PC Ventures used the proceeds from the borrowing to make a $783 million capital contribution to the Operating Partnership. The Operating Partnership accounts for its interest in the Timberland Venture under the equity method of accounting.
	The Timberland Venture is a variable interest entity. The primary operating activities of the Timberland Venture consist of owning timberlands and entering into cutting contracts with an affiliate of the other member. Besides quarterly distributions to PC Ventures which it uses to fund interest payments on the loan owed by PC Ventures, the Operating Partnership has not provided financing or other support to the venture. The venture generates sufficient cash from operating activities to finance its operations.
	We are not the primary beneficiary of the Timberland Venture. PC Member does not manage the day-to-day operations of the Timberland Venture, it has only limited protective rights and its involvement is generally limited to receiving distributions on its preferred and common interests. We are not the primary beneficiary because we do not direct the activities that most significantly impact the Timberland Venture’s economic performance. We believe that the activities that most significantly impact the Timberland Venture’s economic performance include managing the timberlands along with the timing and extent of the harvesting activities, neither of which we control.
	The carrying amount of the investment is $195 million at September 30, 2013 and $204 million at December 31, 2012, and it is reported in the Consolidated Balance Sheets as Equity Investment in Timberland Venture. Our maximum exposure to loss is $195 million, the carrying amount of the investment. Generally, losses are first allocated among the common interests based on positive capital accounts in which we hold a 9% common interest. No losses are allocated to our preferred interest ($705 million) until the common interests have absorbed losses of approximately $861 million.

Summarized_Income_Statement_In

Summarized Income Statement Information of Unconsolidated Subsidiary	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
Summarized Income Statement Information of Affiliate	'
	Summarized Income Statement Information of Unconsolidated Subsidiary
	The earnings of the Timberland Venture are a significant component of consolidated earnings. See Note 13 of the Notes to Consolidated Financial Statements. Equity earnings for the Timberland Venture were $47 million for the nine-month period ending September 30, 2013, and were $42 million for the nine-month period ending September 30, 2012. Equity earnings includes the amortization of the difference between the book value of the company’s investment and its proportionate share of the Timberland Venture’s net assets of $7 million and $6 million for the nine-month periods ended September 30, 2013 and 2012, respectively. Furthermore, interest expense in connection with the loan from the Timberland Venture was $43 million for each of the nine-month periods ended September 30, 2013 and 2012. The table below presents summarized income statement information for the Timberland Venture (in millions):
		Nine Months Ended September 30,
		2013			2012
	Revenues	$	13		$	10
	Cost of Goods Sold (A)	12			11
	Selling, General and Administrative Expenses	4			6
	Operating Income (Loss)	(3		)	(7		)
	Interest Income, net	43			43
	Net Income before Allocation to Preferred and Common Interests	$	40		$	36
	(A)	Cost of Goods Sold includes Depreciation, Depletion and Amortization of $11 million and $10 million for the nine-month periods ended September 30, 2013 and 2012, respectively.
PLUM CREEK TIMBERLANDS L P [Member]	'
Summarized Income Statement Information of Affiliate	'
	Summarized Income Statement Information of Unconsolidated Subsidiary
	The earnings of the Timberland Venture are a significant component of consolidated earnings. See Note 12 of the Notes to Consolidated Financial Statements. Equity earnings for the Timberland Venture were $47 million for the nine-month period ending September 30, 2013, and were $42 million for the nine-month period ending September 30, 2012. Equity earnings includes the amortization of the difference between the book value of the Operating Partnership’s investment and its proportionate share of the Timberland Venture’s net assets of $7 million and $6 million for the nine-month periods ended September 30, 2013 and 2012, respectively. The table below presents summarized income statement information for the Timberland Venture (in millions):
		Nine Months Ended September 30,
		2013			2012
	Revenues	$	13		$	10
	Cost of Goods Sold (A)	12			11
	Selling, General and Administrative Expenses	4			6
	Operating Income (Loss)	(3		)	(7		)
	Interest Income, net	43			43
	Net Income before Allocation to Preferred and Common Interests	$	40		$	36
	(A)	Cost of Goods Sold includes Depreciation, Depletion and Amortization of $11 million and $10 million for the nine-month periods ended September 30, 2013 and 2012, respectively.

Segment_Information

Segment Information	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
Segment Information	'
	Segment Information
	The tables below present information about reported segments for the quarterly and nine-month periods ended September 30 (in millions):
		Northern			Southern			Real		Manufactured		Other (B)		Total (C)
		Resources (A)			Resources			Estate		Products
	Quarter Ended September 30, 2013
	External Revenues	$	60		$	111		$	96	$	94	$	5	$	366
	Intersegment Revenues	7			—			—		—		—		7
	Depreciation, Depletion and Amortization	11			17			1		4		1		34
	Basis of Real Estate Sold	—			—			27		—		—		27
	Other Operating Gain	—			—			—		—		1		1
	Operating Income	5			27			63		11		5		111
	Quarter Ended September 30, 2012
	External Revenues	$	58		$	110		$	96	$	85	$	5	$	354
	Intersegment Revenues	7			—			—		—		—		7
	Depreciation, Depletion and Amortization	7			19			—		4		—		30
	Basis of Real Estate Sold	—			—			36		—		—		36
	Other Operating Gain	—			—			—		—		—		—
	Operating Income	5			23			54		9		5		96
		Northern			Southern			Real		Manufactured		Other (B)		Total (C)
		Resources (A)			Resources			Estate		Products
	Nine Months Ended September 30, 2013
	External Revenues	$	174		$	313		$	227	$	279	$	16	$	1,009
	Intersegment Revenues	20			—			—		—		—		20
	Depreciation, Depletion and Amortization	23			45			1		12		2		83
	Basis of Real Estate Sold	—			—			69		—		—		69
	Other Operating Gain	—			—			—		—		1		1
	Operating Income	24			74			138		35		14		285
	Nine Months Ended September 30, 2012
	External Revenues	$	168		$	312		$	243	$	246	$	16	$	985
	Intersegment Revenues	17			—			—		—		—		17
	Depreciation, Depletion and Amortization	20			52			1		11		—		84
	Basis of Real Estate Sold	—			—			111		—		—		111
	Other Operating Gain	—			—			—		—		—		—
	Operating Income	15			66			113		22		14		230
	(A)	During the third quarter of 2013, the Northern Resources Segment recognized a loss of $4 million related to forest fires, which is included in depreciation, depletion and amortization in the consolidated financial statements.
	(B)	During the third quarter of 2013, the company sold certain mineral reserves for a gain of $1 million. This gain is reported as Other Operating Gain in our Other Segment and is included in Other Operating Income (Expense), net in the Consolidated Statements of Income.
	(C)	Consolidated depreciation, depletion and amortization includes unallocated corporate expense of $1 million for each of the quarterly periods ended September 30, 2013 and September 30, 2012; and $3 million for each of the nine-month periods ended September 30, 2013 and September 30, 2012.
	A reconciliation of total segment operating income to income before income taxes is presented below for the quarterly and nine-month periods ended September 30 (in millions):
		Quarter Ended September 30,
		2013			2012
	Total Segment Operating Income	$	111		$	96
	Corporate and Other Unallocated Expenses	(16		)	(17		)
	Other Unallocated Operating Income (Expense), net	(4		)	—
	Operating Income	91			79
	Equity Earnings from Timberland Venture	16			14
	Total Interest Expense, net	(34		)	(35		)
	Income before Income Taxes	$	73		$	58
		Nine Months Ended September 30,
		2013			2012
	Total Segment Operating Income	$	285		$	230
	Corporate and Other Unallocated Expenses	(51		)	(47		)
	Other Unallocated Operating Income (Expense), net	(3		)	1
	Operating Income	231			184
	Equity Earnings from Timberland Venture	47			42
	Total Interest Expense, net	(104		)	(104		)
	Income before Income Taxes	$	174		$	122
PLUM CREEK TIMBERLANDS L P [Member]	'
Segment Information	'
	Segment Information
	The tables below present information about reported segments for the quarterly and nine-month periods ended September 30 (in millions):
		Northern			Southern			Real		Manufactured		Other (B)		Total (C)
		Resources (A)			Resources			Estate		Products
	Quarter Ended September 30, 2013
	External Revenues	$	60		$	111		$	96	$	94	$	5	$	366
	Intersegment Revenues	7			—			—		—		—		7
	Depreciation, Depletion and Amortization	11			17			1		4		1		34
	Basis of Real Estate Sold	—			—			27		—		—		27
	Other Operating Gain	—			—			—		—		1		1
	Operating Income	5			27			63		11		5		111
	Quarter Ended September 30, 2012
	External Revenues	$	58		$	110		$	96	$	85	$	5	$	354
	Intersegment Revenues	7			—			—		—		—		7
	Depreciation, Depletion and Amortization	7			19			—		4		—		30
	Basis of Real Estate Sold	—			—			36		—		—		36
	Other Operating Gain	—			—			—		—		—		—
	Operating Income	5			23			54		9		5		96
		Northern			Southern			Real		Manufactured		Other (B)		Total (C)
		Resources (A)			Resources			Estate		Products
	Nine Months Ended September 30, 2013
	External Revenues	$	174		$	313		$	227	$	279	$	16	$	1,009
	Intersegment Revenues	20			—			—		—		—		20
	Depreciation, Depletion and Amortization	23			45			1		12		2		83
	Basis of Real Estate Sold	—			—			69		—		—		69
	Other Operating Gain	—			—			—		—		1		1
	Operating Income	24			74			138		35		14		285
	Nine Months Ended September 30, 2012
	External Revenues	$	168		$	312		$	243	$	246	$	16	$	985
	Intersegment Revenues	17			—			—		—		—		17
	Depreciation, Depletion and Amortization	20			52			1		11		—		84
	Basis of Real Estate Sold	—			—			111		—		—		111
	Other Operating Gain	—			—			—		—		—		—
	Operating Income	15			66			113		22		14		230
	(A)	During the third quarter of 2013, the Northern Resources Segment recognized a loss of $4 million related to forest fires, which is included in depreciation, depletion and amortization in the consolidated financial statements.
	(B)	During the third quarter of 2013, the Operating Partnership sold certain mineral reserves for a gain of $1 million. This gain is reported as Other Operating Gain in our Other Segment and is included in Other Operating Income (Expense), net in the Consolidated Statements of Income.
	(C)	Consolidated depreciation, depletion and amortization includes unallocated corporate expense of $1 million for each of the quarterly periods ended September 30, 2013 and September 30, 2012; and $3 million for each of the nine-month periods ended September 30, 2013 and September 30, 2012.
	A reconciliation of total segment operating income to income before income taxes is presented below for the quarterly and nine-month periods ended September 30 (in millions):
		Quarter Ended September 30,
		2013			2012
	Total Segment Operating Income	$	111		$	96
	Corporate and Other Unallocated Expenses	(16		)	(17		)
	Other Unallocated Operating Income (Expense), net	(4		)	—
	Operating Income	91			79
	Equity Earnings from Timberland Venture	16			14
	Interest Expense, net	(20		)	(21		)
	Income before Income Taxes	$	87		$	72
		Nine Months Ended September 30,
		2013			2012
	Total Segment Operating Income	$	285		$	230
	Corporate and Other Unallocated Expenses	(51		)	(47		)
	Other Unallocated Operating Income (Expense), net	(3		)	1
	Operating Income	231			184
	Equity Earnings from Timberland Venture	47			42
	Interest Expense, net	(61		)	(61		)
	Income before Income Taxes	$	217		$	165

Subsequent_Events

Subsequent Events	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
Subsequent Events [Text Block]	'
	Subsequent Events
	Quarterly Dividend. On November 5, 2013, the Board of Directors authorized the company to make a dividend payment of $0.44 per share, or approximately $78 million, which will be paid on November 27, 2013 to stockholders of record on November 15, 2013.
	Timberland Acquisition and Equity Offering. On October 28, 2013, the company announced an agreement to purchase approximately 501,000 acres of timberlands together with ownership interests in 109,000 acres of development-quality lands from MeadWestvaco Corporation for a total purchase price of approximately $1.1 billion. The 501,000 acres of timberlands are located in Alabama, Georgia, South Carolina, Virginia, and West Virginia and include certain subsurface rights, mineral rights, and wind power assets. The 109,000 acres of development-quality lands are located near Charleston, South Carolina, of which the company is acquiring a 50% interest in approximately 87,000 acres and a 5% interest in approximately 22,000 acres. The company expects to account for this acquisition as a business combination and expects that its ownership interests in the development-quality lands will be accounted for under the equity method of accounting.
	The company is acquiring the assets by paying cash of $226 million and issuing MeadWestvaco Corporation an $860 million ten-year, fixed rate, installment note based on market interest rates at closing. The company expects to close this transaction during the fourth quarter of this year.
	The company also announced an equity offering on October 28, 2013. On November 4, 2013, the company completed the equity offering resulting in the issuance of 13,915,000 additional shares of common stock for net proceeds of $606 million. The proceeds from the equity offering are expected to be used to pay the cash portion of the acquisition and the acquisition related transaction fees, with the balance used to pay down approximately $375 million of the company’s outstanding debt, including a $225 million pay down of the Term Credit Agreement.
PLUM CREEK TIMBERLANDS L P [Member]	'
Subsequent Events [Text Block]	'
	Subsequent Events
	Timberland Acquisition and Equity Offering. On October 28, 2013, Plum Creek, along with the Operating Partnership, announced an agreement to purchase approximately 501,000 acres of timberlands together with ownership interests in 109,000 acres of development-quality lands from MeadWestvaco Corporation for a total purchase price of approximately $1.1 billion. The 501,000 acres of timberlands are located in Alabama, Georgia, South Carolina, Virginia, and West Virginia and include certain subsurface rights, mineral rights, and wind power assets. The 109,000 acres of development-quality lands are located near Charleston, South Carolina, of which the Operating Partnership is acquiring a 50% interest in approximately 87,000 acres and a 5% interest in approximately 22,000 acres. The Operating Partnership expects to account for this acquisition as a business combination and expects that its ownership interests in the development-quality lands will be accounted for under the equity method of accounting.
	The Operating Partnership is acquiring the assets by paying cash of $226 million and issuing MeadWestvaco Corporation an $860 million, ten-year, fixed rate, installment note based on market interest rates at closing. The Operating Partnership expects to close this transaction during the fourth quarter of this year.
	In conjunction with the above, Plum Creek announced an equity offering on October 28, 2013. On November 4, 2013, Plum Creek completed the equity offering resulting in the issuance of 13,915,000 additional shares of common stock for net proceeds of $606 million. The proceeds from the equity offering are expected to be used to pay the cash portion of the acquisition and the acquisition related transaction fees, with the balance used to pay down approximately $375 million of the Operating Partnership’s outstanding debt, including a $225 million pay down of the Term Credit Agreement.

Supplemental_Disclosures

Supplemental Disclosures	9 Months Ended
	Sep. 30, 2013
Supplemental Disclosures Abstract	'
Supplemental Disclosures	'
	FINANCIAL STATEMENTS (CONTINUED)
	Included in this item are the consolidated financial statements related to Plum Creek Timberlands, L.P., a Delaware Limited Partnership and a wholly-owned subsidiary of Plum Creek Timber Company, Inc. These financial statements are provided pursuant to Rule 3-10 of Regulation S-X in connection with the shelf registration statement on Form S-3 filed in December of 2011 pursuant to which Plum Creek Timberlands, L.P. has registered and from time to time may offer and sell debt securities. As of September 30, 2013, Plum Creek Timberlands, L.P. has publicly issued and outstanding $1,358 million aggregate principal amount of Senior Notes ("Public Debt") pursuant to the shelf registration statement.

Basis_of_Presentation_Accounti

Basis of Presentation (Accounting Policies)	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
New Accounting Pronouncements, Policy [Policy Text Block]	'
	New Accounting Pronouncements
	Presentation of Items Reclassified from Accumulated Other Comprehensive Income (AOCI). In 2013, the FASB issued new guidance requiring entities to disclose in a single location (either on the face of the income statement or in the footnotes) the effects of reclassifications out of AOCI. For items reclassified out of AOCI and into net income in their entirety, such as realized gains or losses on the company's available-for-sale securities, entities must disclose the effect of the reclassification on each affected net income item. For AOCI reclassification items not reclassified in their entirety into net income, such as amortization of the actuarial net loss on the company's defined benefit pension plans, entities must provide a cross reference to the notes in other disclosures that already provide information about those amounts. The new guidance is effective for annual reporting periods beginning after December 15, 2012, and interim periods within those years. The adoption did not have a material impact on the company's financial position, results of operations or cash flows. See Note 9 of the Notes to Consolidated Financial Statements.
PLUM CREEK TIMBERLANDS L P [Member]	'
Consolidation, Subsidiaries or Other Investments, Consolidated Entities, Policy [Policy Text Block]	'
	The consolidated financial statements of the Operating Partnership include the accounts of Plum Creek Timberlands, L.P. and its subsidiaries. The Operating Partnership is 100% owned by Plum Creek. Plum Creek has no assets or liabilities other than its direct and indirect ownership interests in Plum Creek Timberlands, L.P. and its interest in Plum Creek Ventures I, LLC (“PC Ventures”), a 100% owned subsidiary of Plum Creek. The Parent has no operations other than its investment in these subsidiaries and transactions in its own equity, such as the issuance and/or repurchase of common stock and the receipt of proceeds from stock option exercises. Intercompany transactions and accounts between Plum Creek Timberlands, L.P. and its subsidiaries have been eliminated in consolidation. All transactions are denominated in United States dollars.
New Accounting Pronouncements, Policy [Policy Text Block]	'
	New Accounting Pronouncements
	Presentation of Items Reclassified from Accumulated Other Comprehensive Income (AOCI). In 2013, the FASB issued new guidance requiring entities to disclose in a single location (either on the face of the income statement or in the footnotes) the effects of reclassifications out of AOCI. For items reclassified out of AOCI and into net income in their entirety, such as realized gains or losses on the Operating Partnership's available-for-sale securities, entities must disclose the effect of the reclassification on each affected net income item. For AOCI reclassification items not reclassified in their entirety into net income, such as amortization of the actuarial net loss on the Operating Partnership's defined benefit pension plans, entities must provide a cross reference to
	the notes in other disclosures that already provide information about those amounts. The new guidance is effective for annual reporting periods beginning after December 15, 2012, and interim periods within those years. The adoption did not have a material impact on the Operating Partnership's financial position, results of operations or cash flows. See Note 8 of the Notes to Consolidated Financial Statements.

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 2013
Earnings Per Share [Abstract]	'
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]	'
	The following table sets forth the reconciliation of basic and diluted earnings per share for the quarterly and nine-month periods ended September 30 (in millions, except per share amounts):
		Quarter Ended September 30,
		2013			2012
	Net Income Available to Common Stockholders	$	72		$	59
	Denominator for Basic Earnings per Share	163			161.5
	Effect of Dilutive Securities – Stock Options	0.3			0.3
	Effect of Dilutive Securities – Restricted Stock Units and Value Management Plan	0.1			0.1
	Denominator for Diluted Earnings per Share – Adjusted for Dilutive Securities	163.4			161.9
	Per Share Amounts:
	Net Income Per Share – Basic	$	0.44		$	0.36
	Net Income Per Share – Diluted	$	0.44		$	0.36
		Nine Months Ended September 30,
		2013			2012
	Net Income Available to Common Stockholders	$	174		$	124
	Denominator for Basic Earnings per Share	162.7			161.5
	Effect of Dilutive Securities – Stock Options	0.4			0.3
	Effect of Dilutive Securities – Restricted Stock Units and Value Management Plan	0.1			—
	Denominator for Diluted Earnings per Share – Adjusted for Dilutive Securities	163.2			161.8
	Per Share Amounts:
	Net Income Per Share - Basic	$	1.06		$	0.77
	Net Income Per Share - Diluted	$	1.06		$	0.76
Antidilutive Options	'
	Antidilutive options were excluded for certain periods from the computation of diluted earnings per share because the exercise prices of the options were greater than the average market price of the common shares. Antidilutive options were as follows for the quarterly and nine-month periods ended September 30 (shares in millions):
		Quarter Ended September 30,
		2013		2012
	Number of Options	—		1.1
	Range of Exercise Prices	N/A		$41.55 to $43.23
	Expiration on or before	N/A		Feb-21
		Nine Months Ended September 30,
		2013		2012
	Number of Options	—		1.1
	Range of Exercise Prices	N/A		$41.55 to $43.23
	Expiration on or before	N/A		Feb-21

Inventories_Tables

Inventories (Tables)	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
Inventory [Line Items]	'
Schedule of Inventory, Current [Table Text Block]	'
	Inventories, accounted for using the lower of average cost or market, consisted of the following (in millions):
		September 30, 2013		December 31, 2012
	Raw Materials (primarily logs)	$	8	$	9
	Work-In-Process	2		2
	Finished Goods	29		24
		39		35
	Supplies	14		14
	Total	$	53	$	49
PLUM CREEK TIMBERLANDS L P [Member]	'
Inventory [Line Items]	'
Schedule of Inventory, Current [Table Text Block]	'
	Inventories, accounted for using the lower of average cost or market, consisted of the following (in millions):
		September 30, 2013		December 31, 2012
	Raw Materials (primarily logs)	$	8	$	9
	Work-In-Process	2		2
	Finished Goods	29		24
		39		35
	Supplies	14		14
	Total	$	53	$	49

Timber_and_Timberlands_Tables

Timber and Timberlands (Tables)	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
Timber and Timberlands [Line Items]	'
Timber and Timberlands Tables	'
	Timber and Timberlands consisted of the following (in millions):
		September 30, 2013		December 31, 2012
	Timber and Logging Roads, net	$	2,162	$	2,169
	Timber Deeds, net	100		92
	Timberlands	1,133		1,102
	Timber and Timberlands, net	$	3,395	$	3,363
PLUM CREEK TIMBERLANDS L P [Member]	'
Timber and Timberlands [Line Items]	'
Timber and Timberlands Tables	'
	Timber and Timberlands consisted of the following (in millions):
		September 30, 2013		December 31, 2012
	Timber and Logging Roads, net	$	2,162	$	2,169
	Timber Deeds, net	100		92
	Timberlands	1,133		1,102
	Timber and Timberlands, net	$	3,395	$	3,363

Property_Plant_and_Equipment_T

Property, Plant and Equipment (Tables)	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
Property, Plant and Equipment [Line Items]	'
Property, Plant and Equipment	'
	Property, Plant and Equipment consisted of the following (in millions):
		September 30, 2013			December 31, 2012
	Land, Buildings and Improvements	$	88		$	88
	Machinery and Equipment	326			318
		414			406
	Accumulated Depreciation	(296		)	(279		)
	Property, Plant and Equipment, net	$	118		$	127
PLUM CREEK TIMBERLANDS L P [Member]	'
Property, Plant and Equipment [Line Items]	'
Property, Plant and Equipment	'
	Property, Plant and Equipment consisted of the following (in millions):
		September 30, 2013			December 31, 2012
	Land, Buildings and Improvements	$	88		$	88
	Machinery and Equipment	326			318
		414			406
	Accumulated Depreciation	(296		)	(279		)
	Property, Plant and Equipment, net	$	118		$	127

Borrowings_Tables

Borrowings (Tables)	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
Debt Instrument [Line Items]	'
Debt	'
	Debt consisted of the following (in millions):
		September 30, 2013		December 31, 2012
	Variable Rate Debt
	Term Credit Agreement (A)	$	450	$	450
	Revolving Line of Credit (B)	507		104
	Fixed Rate Debt
	Senior Notes	1,439		1,613
	Note Payable to Timberland Venture	783		783
	Total Debt	3,179		2,950
	Less:
	Current Portion of Long-Term Debt	74		248
	Line of Credit	507		104
	Long-Term Portion	$	2,598	$	2,598
	(A)	The company has a $450 million term credit agreement that matures on April 3, 2019. The interest rate on the $450 million term credit agreement was 1.68% and 1.71% as of September 30, 2013 and December 31, 2012, respectively. After giving effect to expected patronage distributions, the effective net interest rate on the term loan was approximately 1% as of both September 30, 2013 and December 31, 2012. On November 4, 2013, the company repaid $225 million of borrowings outstanding under the term credit agreement. See Note 16 of the Notes to Consolidated Financial Statements.
	(B)	The weighted-average interest rate for the borrowings on the line of credit was 1.38% and 1.43% as of September 30, 2013 and December 31, 2012, respectively. As of September 30, 2013, we had $507 million of borrowings and $1 million of standby letters of credit outstanding; $192 million remained available for borrowing under our $700 million line of credit. As of October 1, 2013, $355 million of the borrowings outstanding under our line of credit was repaid.
PLUM CREEK TIMBERLANDS L P [Member]	'
Debt Instrument [Line Items]	'
Debt	'
	Debt consisted of the following (in millions):
		September 30, 2013		December 31, 2012
	Variable Rate Debt
	Term Credit Agreement (A)	$	450	$	450
	Revolving Line of Credit (B)	507		104
	Fixed Rate Debt
	Senior Notes	1,439		1,613
	Total Debt	2,396		2,167
	Less:
	Current Portion of Long-Term Debt	74		248
	Line of Credit	507		104
	Long-Term Portion	$	1,815	$	1,815
	(A)	The Operating Partnership has a $450 million term credit agreement that matures on April 3, 2019. The interest rate on the $450 million term credit agreement was 1.68% and 1.71% as of September 30, 2013 and December 31, 2012, respectively. After giving effect to expected patronage distributions, the effective net interest rate on the term loan was approximately 1% as of both September 30, 2013 and December 31, 2012. On November 4, 2013, the Operating Partnership repaid $225 million of borrowings outstanding under the term credit agreement. See Note 15 of the Notes to Consolidated Financial Statements.
	(B)	The weighted-average interest rate for the borrowings on the line of credit was 1.38% and 1.43% as of September 30, 2013 and December 31, 2012, respectively. As of September 30, 2013, we had $507 million of borrowings and $1 million of standby letters of credit outstanding; $192 million remained available for borrowing under our $700 million line of credit. As of October 1, 2013, $355 million of the borrowings outstanding under our line of credit was repaid.

Stockholders_Equity_Tables

Stockholders' Equity (Tables) (PLUM CREEK TIMBER CO INC [Member])	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
Stockholders' Equity [Line Items]	'
Schedule of Stockholders Equity [Table Text Block]	'
	The changes in the company’s stockholders’ equity accounts were as follows during 2013 (in millions):
		Common Stock											Retained						Accumulated
													Earnings (Accumulated Deficit)						Other
																			Comprehensive
		Shares			Dollars				Paid-in							Treasury			Income (Loss)			Total
									Capital							Stock						Equity
	January 1, 2013	162			$	2			$	2,288			$	(97	)	$	(938	)	$	(32	)	$	1,223
	Net Income												56									56
	Other Comprehensive Income (Loss)																		3			3
	Dividends												(68		)							(68		)
	Stock Option Exercises	0.6			—				25													25
	Shares Issued under Stock Incentive Plans	0.1			—				—													—
	Share-based Compensation								3													3
	Common Stock Repurchased	—			—											(2		)				(2		)
	March 31, 2013	162.7			$	2			$	2,316			$	(109	)	$	(940	)	$	(29	)	$	1,240
	Net Income												46									46
	Other Comprehensive Income (Loss)																		2			2
	Dividends												(72		)							(72		)
	Stock Option Exercises	0.3			—				10													10
	Share-based Compensation								2													2
	June 30, 2013	163			$	2			$	2,328			$	(135	)	$	(940	)	$	(27	)	$	1,228
	Net Income												72									72
	Other Comprehensive Income (Loss)																		—			—
	Dividends												(72		)							(72		)
	Share-based Compensation								2													2
	September 30, 2013	163			$	2			$	2,330			$	(135	)	$	(940	)	$	(27	)	$	1,230
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]	'
	The changes in the company’s accumulated other comprehensive income by component, net of tax, were as follows during 2013 (in millions):
		Net Unrealized Holding Gains (Losses)				Defined Benefit Plan Actuarial Net Loss				Total
	January 1, 2013	$	8			$	(40	)		$	(32	)
	Other Comprehensive Income (Loss) before Reclassifications	2				—				2
	Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	—				1				1
	31-Mar-13	$	10			$	(39	)		$	(29	)
	Other Comprehensive Income (Loss) before Reclassifications	1				—				1
	Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	—				1				1
	30-Jun-13	$	11			$	(38	)		$	(27	)
	Other Comprehensive Income (Loss) before Reclassifications	(1		)		—				(1		)
	Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	—				1				1
	30-Sep-13	$	10			$	(37	)		$	(27	)
Reclassification out of Accumulated Other Comprehensive Income [Table Text Block]	'
	Summarized below are the reclassifications out of accumulated other comprehensive income for the quarter ended September 30, 2013 (in millions):
	Details about Accumulated Other Comprehensive Income Components	Amount Reclassified from Accumulated Other Comprehensive Income				Affected Line Items in the Statement Where Net Income is Presented
	Amortization of Actuarial Loss	$	1			See Note 11 - Employee Pension Plans
	Total	$	1
	Summarized below are the reclassifications out of accumulated other comprehensive income for the nine months ended September 30, 2013 (in millions):
	Details about Accumulated Other Comprehensive Income Components	Amount Reclassified from Accumulated Other Comprehensive Income				Affected Line Items in the Statement Where Net Income is Presented
	Amortization of Actuarial Loss	$	3			See Note 11 - Employee Pension Plans
	Total	$	3

Partners_Capital_Tables

Partners' Capital (Tables) (PLUM CREEK TIMBERLANDS L P [Member])	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBERLANDS L P [Member]	'
Partners' Capital [Line Items]	'
Schedule Of Components Of Partners' Capital	'
	The changes in the Operating Partnership’s capital accounts were as follows during 2013 (in millions):
		Preferred			Common			Accumulated			Total
		Partnership			Partners’			Other			Partnership
		Interest			Capital			Comprehensive			Capital
								Income (Loss)
	January 1, 2013	$	790		$	1,255		$	(32	)	$	2,013
	Net Income before Allocation to Series T-1 Preferred Interest and Partners				70						70
	Other Comprehensive Income (Loss)							3			3
	Net Income Allocation to Series T-1 Preferred Interest	14			(14		)				—
	Distributions to Partners (Common Partnership Interests)				(45		)				(45		)
	Distributions for Series T-1 Preferred Interest	(14		)							(14		)
	Capital Contributions from Parent				3						3
	March 31, 2013	$	790		$	1,269		$	(29	)	$	2,030
	Net Income before Allocation to Series T-1 Preferred Interest and Partners				61						61
	Other Comprehensive Income (Loss)							2			2
	Net Income Allocation to Series T-1 Preferred Interest	15			(15		)				—
	Distributions to Partners (Common Partnership Interests)				(62		)				(62		)
	Distributions for Series T-1 Preferred Interest	(15		)							(15		)
	Capital Contributions from Parent				2						2
	June 30, 2013	$	790		$	1,255		$	(27	)	$	2,018
	Net Income before Allocation to Series T-1 Preferred Interest and Partners				86						86
	Other Comprehensive Income (Loss)							—			—
	Net Income Allocation to Series T-1 Preferred Interest	14			(14		)				—
	Distributions to Partners (Common Partnership Interests)				(72		)				(72		)
	Distributions for Series T-1 Preferred Interest	(14		)							(14		)
	Capital Contributions from Parent				2						2
	September 30, 2013	$	790		$	1,257		$	(27	)	$	2,020
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]	'
	The changes in the Operating Partnership's accumulated other comprehensive income by component, net of tax, were as follows during 2013 (in millions):
		Net Unrealized Holding Gains (Losses)			Defined Benefit Plan Actuarial Net Loss			Total
	January 1, 2013	$	8		$	(40	)	$	(32	)
	Other Comprehensive Income (Loss) before Reclassifications	2			—			2
	Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	—			1			1
	31-Mar-13	$	10		$	(39	)	$	(29	)
	Other Comprehensive Income (Loss) before Reclassifications	1			—			1
	Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	—			1			1
	30-Jun-13	$	11		$	(38	)	$	(27	)
	Other Comprehensive Income (Loss) before Reclassifications	(1		)	—			(1		)
	Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	—			1			1
	30-Sep-13	$	10		$	(37	)	$	(27	)
Reclassification out of Accumulated Other Comprehensive Income [Table Text Block]	'
	Summarized below are the reclassifications out of accumulated other comprehensive income for the quarter ended September 30, 2013 (in millions):
	Details about Accumulated Other Comprehensive Income Components	Amount Reclassified from Accumulated Other Comprehensive Income			Affected Line Items in the Statement Where Net Income is Presented
	Amortization of Actuarial Loss	$	1		See Note 10 - Employee Pension Plans
	Total	$	1
	Summarized below are the reclassifications out of accumulated other comprehensive income for the nine months ended September 30, 2013 (in millions):
	Details about Accumulated Other Comprehensive Income Components	Amount Reclassified from Accumulated Other Comprehensive Income			Affected Line Items in the Statement Where Net Income is Presented
	Amortization of Actuarial Loss	3			See Note 10 - Employee Pension Plans
	Total	$	3

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'
Level 1 Assets Reported in the Company's Financial Statements at Fair Value, Measured on a Recurring Basis	'
	Assets and Liabilities Measured at Fair Value on a Recurring Basis. The company’s fair value measurements of its cash equivalents, available-for-sale securities, and trading securities, measured on a recurring basis, are categorized as Level 1 measurements under the fair value hierarchy in the Accounting Standards Codification. A Level 1 valuation is based on quoted prices in active markets at the measurement date for identical unrestricted assets or liabilities. Summarized below are the Level 1 assets reported in the company’s financial statements at fair value, measured on a recurring basis (in millions):
		Balance at			Fair Value Measurements
		30-Sep-13			at Reporting Date Using
					Quoted Prices in Active
					Markets of Identical Assets
					(Level 1 Measurements)
	Cash Equivalents (A)	$	434		$	434
	Available-for-Sale Securities (B)	37			37
	Trading Securities (B)	5			5
	Total	$	476		$	476
		Balance at			Fair Value Measurements
		31-Dec-12			at Reporting Date Using
					Quoted Prices in Active
					Markets of Identical Assets
					(Level 1 Measurements)
	Cash Equivalents (A)	$	354		$	354
	Available-for-Sale Securities (B)	34			34
	Trading Securities (B)	5			5
	Total	$	393		$	393
	(A)	Consists of several money market funds and is included in the $439 million and $356 million of Cash and Cash Equivalents in the Consolidated Balance Sheets at September 30, 2013 and December 31, 2012, respectively.
	(B)	Consists of several mutual funds and is included in Investment in Grantor Trusts in the Consolidated Balance Sheets at September 30, 2013 and December 31, 2012. At September 30, 2013, investments in these mutual funds were approximately 45% in domestic (U.S.) equities, 25% in international equities and 30% in debt securities.
Fair Value, Liabilities Measured on Recurring Basis [Table Text Block]	'
	Other Instruments. The carrying amount of notes receivable approximates fair value due to the short-term maturities of these instruments. Summarized below are the carrying amount and fair value of the company's debt (estimated using the discounted cash flows method) along with the categorization under the fair value hierarchy in the Accounting Standards Codification (in millions):
						Fair Value at September 30, 2013
			Carrying Amount at September 30, 2013			Quoted Prices		Significant		Significant		Total
						In Active		Observable		Unobservable
						Markets for		Inputs		Inputs
						Identical Assets		(Level 2)		(Level 3)
						(Level 1)
	Public Debt (A)		$	1,353		$	—	$	1,387	$	—	$	1,387
	Private Debt (B)		86			—		88		—		88
	Term Credit Agreement (C)		450			—		450		—		450
	Line of Credit (D)		507			—		507		—		507
	Note Payable to Timberland Venture (E)		783			—		—		926		926
	Total Debt		$	3,179		$	—	$	2,432	$	926	$	3,358
						Fair Value at December 31, 2012
			Carrying Amount at			Quoted Prices		Significant		Significant		Total
			31-Dec-12			In Active		Observable		Unobservable
						Markets for		Inputs		Inputs
						Identical Assets		(Level 2)		(Level 3)
						(Level 1)
	Public Debt (A)		$	1,353		$	—	$	1,465	$	—	$	1,465
	Private Debt (B)		260			—		266		—		266
	Term Credit Agreement (C)		450			—		450		—		450
	Line of Credit (D)		104			—		104		—		104
	Note Payable to Timberland Venture (E)		783			—		—		973		973
	Total Debt		$	2,950		$	—	$	2,285	$	973	$	3,258
	(A)	Fair value of the company's Public Debt (publicly issued Senior Notes) is estimated using multiple market quotes for the company's public bonds.
	(B)	Fair value of the company's Private Debt (Senior Notes with various maturities and fixed interest rates which are privately placed with various lenders) is estimated using market quotes for the company's Public Debt adjusted for the different maturities and an illiquidity premium.
	(C)	Fair value is estimated by adjusting the spread over LIBOR to a current market quote for comparable debt.
	(D)	Fair value is estimated by adjusting the spread over LIBOR to a current market quote for comparable credit lines.
	(E)	Fair value is estimated by using market quotes for the company's Public Debt adjusted by an estimated risk premium for holding company debt and the different maturity.
PLUM CREEK TIMBERLANDS L P [Member]	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'
Level 1 Assets Reported in the Company's Financial Statements at Fair Value, Measured on a Recurring Basis	'
	Assets and Liabilities Measured at Fair Value on a Recurring Basis. The Operating Partnership’s fair value measurements of its cash equivalents, available-for-sale securities, and trading securities, measured on a recurring basis, are categorized as Level 1 measurements under the fair value hierarchy in the Accounting Standards Codification. A Level 1 valuation is based on quoted prices in active markets at the measurement date for identical unrestricted assets or liabilities. Summarized below are the Level 1 assets reported in the Operating Partnership’s financial statements at fair value, measured on a recurring basis (in millions):
		Balance at			Fair Value Measurements
		30-Sep-13			at Reporting Date Using
					Quoted Prices in Active
					Markets of Identical Assets
					(Level 1 Measurements)
	Cash Equivalents (A)	$	434		$	434
	Available-for-Sale Securities (B)	37			37
	Trading Securities (B)	5			5
	Total	$	476		$	476
		Balance at			Fair Value Measurements
		31-Dec-12			at Reporting Date Using
					Quoted Prices in Active
					Markets of Identical Assets
					(Level 1 Measurements)
	Cash Equivalents (A)	$	354		$	354
	Available-for-Sale Securities (B)	34			34
	Trading Securities (B)	5			5
	Total	$	393		$	393
	(A)	Consists of several money market funds and is included in the $439 million and $356 million of Cash and Cash Equivalents in the Consolidated Balance Sheets at September 30, 2013 and December 31, 2012, respectively.
	(B)	Consists of several mutual funds and is included in Investment in Grantor Trusts in the Consolidated Balance Sheets at September 30, 2013 and December 31, 2012. At September 30, 2013, investments in these mutual funds were approximately 45% in domestic (U.S.) equities, 25% in international equities and 30% in debt securities.
Fair Value, Liabilities Measured on Recurring Basis [Table Text Block]	'
	Other Instruments. The carrying amount of notes receivable approximates fair value due to the short-term maturities of these instruments. Summarized below are the carrying amount and fair value of the Operating Partnership's debt (estimated using the discounted cash flows method) along with the categorization under the fair value hierarchy in the Accounting Standards Codification (in millions):
						Fair Value at September 30, 2013
			Carrying Amount at September 30, 2013			Quoted Prices		Significant		Significant		Total
						In Active		Observable		Unobservable
						Markets for		Inputs		Inputs
						Identical Assets		(Level 2)		(Level 3)
						(Level 1)
	Public Debt (A)		$	1,353		$	—	$	1,387	$	—	$	1,387
	Private Debt (B)		86			—		88		—		88
	Term Credit Agreement (C)		450			—		450		—		450
	Line of Credit (D)		507			—		507		—		507
	Total Debt		$	2,396		$	—	$	2,432	$	—	$	2,432
						Fair Value at December 31, 2012
			Carrying Amount at			Quoted Prices		Significant		Significant		Total
			31-Dec-12			In Active		Observable		Unobservable
						Markets for		Inputs		Inputs
						Identical Assets		(Level 2)		(Level 3)
						(Level 1)
	Public Debt (A)		$	1,353		$	—	$	1,465	$	—	$	1,465
	Private Debt (B)		260			—		266		—		266
	Term Credit Agreement (C)		450			—		450		—		450
	Line of Credit (D)		104			—		104		—		104
	Total Debt		$	2,167		$	—	$	2,285	$	—	$	2,285
	(A)	Fair value of the Operating Partnership's Public Debt (publicly issued Senior Notes) is estimated using multiple market quotes for the Operating Partnership's public bonds.
	(B)	Fair value of the Operating Partnership's Private Debt (Senior Notes with various maturities and fixed interest rates which are privately placed with various lenders) is estimated using market quotes for the Operating Partnership's Public Debt adjusted for the different maturities and an illiquidity premium.
	(C)	Fair value is estimated by adjusting the spread over LIBOR to a current market quote for comparable debt.
	(D)	Fair value is estimated by adjusting the spread over LIBOR to a current market quote for comparable credit lines.

Employee_Pension_Plans_Tables

Employee Pension Plans (Tables)	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
Defined Benefit Plan Disclosure [Line Items]	'
Schedule of Net Benefit Costs [Table Text Block]	'
	The components of pension cost were as follows for the quarterly and nine-month periods ended September 30 (in millions):
		Quarter Ended September 30,
		2013			2012
	Service Cost	$	2		$	2
	Interest Cost	2			2
	Expected Return on Plan Assets	(2		)	(2		)
	Recognized Actuarial Loss	1			1
	Total Pension Cost	$	3		$	3
		Nine Months Ended September 30,
		2013			2012
	Service Cost	$	6		$	6
	Interest Cost	6			6
	Expected Return on Plan Assets	(6		)	(6		)
	Recognized Actuarial Loss	3			3
	Total Pension Cost	$	9		$	9
PLUM CREEK TIMBERLANDS L P [Member]	'
Defined Benefit Plan Disclosure [Line Items]	'
Schedule of Net Benefit Costs [Table Text Block]	'
	The components of pension cost were as follows for the quarterly and nine-month periods ended September 30 (in millions):
		Quarter Ended September 30,
		2013			2012
	Service Cost	$	2		$	2
	Interest Cost	2			2
	Expected Return on Plan Assets	(2		)	(2		)
	Recognized Actuarial Loss	1			1
	Total Pension Cost	$	3		$	3
		Nine Months Ended September 30,
		2013			2012
	Service Cost	$	6		$	6
	Interest Cost	6			6
	Expected Return on Plan Assets	(6		)	(6		)
	Recognized Actuarial Loss	3			3
	Total Pension Cost	$	9		$	9

Summarized_Income_Statement_In1

Summarized Income Statement Information of Unconsolidated Subsidiary (Tables)	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
Schedule of Equity Method Investments [Line Items]	'
Schedule of Summarized Income Statement of Affiliate	'
	The table below presents summarized income statement information for the Timberland Venture (in millions):
		Nine Months Ended September 30,
		2013			2012
	Revenues	$	13		$	10
	Cost of Goods Sold (A)	12			11
	Selling, General and Administrative Expenses	4			6
	Operating Income (Loss)	(3		)	(7		)
	Interest Income, net	43			43
	Net Income before Allocation to Preferred and Common Interests	$	40		$	36
	(A)	Cost of Goods Sold includes Depreciation, Depletion and Amortization of $11 million and $10 million for the nine-month periods ended September 30, 2013 and 2012, respectively.
PLUM CREEK TIMBERLANDS L P [Member]	'
Schedule of Equity Method Investments [Line Items]	'
Schedule of Summarized Income Statement of Affiliate	'
	The table below presents summarized income statement information for the Timberland Venture (in millions):
		Nine Months Ended September 30,
		2013			2012
	Revenues	$	13		$	10
	Cost of Goods Sold (A)	12			11
	Selling, General and Administrative Expenses	4			6
	Operating Income (Loss)	(3		)	(7		)
	Interest Income, net	43			43
	Net Income before Allocation to Preferred and Common Interests	$	40		$	36
	(A)	Cost of Goods Sold includes Depreciation, Depletion and Amortization of $11 million and $10 million for the nine-month periods ended September 30, 2013 and 2012, respectively.

Segment_Information_Tables

Segment Information (Tables)	9 Months Ended
	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
Segment Reporting Information [Line Items]	'
Schedule of Segment Reporting Information, by Segment [Table Text Block]	'
	The tables below present information about reported segments for the quarterly and nine-month periods ended September 30 (in millions):
		Northern			Southern			Real		Manufactured		Other (B)		Total (C)
		Resources (A)			Resources			Estate		Products
	Quarter Ended September 30, 2013
	External Revenues	$	60		$	111		$	96	$	94	$	5	$	366
	Intersegment Revenues	7			—			—		—		—		7
	Depreciation, Depletion and Amortization	11			17			1		4		1		34
	Basis of Real Estate Sold	—			—			27		—		—		27
	Other Operating Gain	—			—			—		—		1		1
	Operating Income	5			27			63		11		5		111
	Quarter Ended September 30, 2012
	External Revenues	$	58		$	110		$	96	$	85	$	5	$	354
	Intersegment Revenues	7			—			—		—		—		7
	Depreciation, Depletion and Amortization	7			19			—		4		—		30
	Basis of Real Estate Sold	—			—			36		—		—		36
	Other Operating Gain	—			—			—		—		—		—
	Operating Income	5			23			54		9		5		96
		Northern			Southern			Real		Manufactured		Other (B)		Total (C)
		Resources (A)			Resources			Estate		Products
	Nine Months Ended September 30, 2013
	External Revenues	$	174		$	313		$	227	$	279	$	16	$	1,009
	Intersegment Revenues	20			—			—		—		—		20
	Depreciation, Depletion and Amortization	23			45			1		12		2		83
	Basis of Real Estate Sold	—			—			69		—		—		69
	Other Operating Gain	—			—			—		—		1		1
	Operating Income	24			74			138		35		14		285
	Nine Months Ended September 30, 2012
	External Revenues	$	168		$	312		$	243	$	246	$	16	$	985
	Intersegment Revenues	17			—			—		—		—		17
	Depreciation, Depletion and Amortization	20			52			1		11		—		84
	Basis of Real Estate Sold	—			—			111		—		—		111
	Other Operating Gain	—			—			—		—		—		—
	Operating Income	15			66			113		22		14		230
	(A)	During the third quarter of 2013, the Northern Resources Segment recognized a loss of $4 million related to forest fires, which is included in depreciation, depletion and amortization in the consolidated financial statements.
	(B)	During the third quarter of 2013, the company sold certain mineral reserves for a gain of $1 million. This gain is reported as Other Operating Gain in our Other Segment and is included in Other Operating Income (Expense), net in the Consolidated Statements of Income.
	(C)	Consolidated depreciation, depletion and amortization includes unallocated corporate expense of $1 million for each of the quarterly periods ended September 30, 2013 and September 30, 2012; and $3 million for each of the nine-month periods ended September 30, 2013 and September 30, 2012.
Reconciliation of Total Segment Operating Income to Consolidated Income Before Income Taxes	'
	A reconciliation of total segment operating income to income before income taxes is presented below for the quarterly and nine-month periods ended September 30 (in millions):
		Quarter Ended September 30,
		2013			2012
	Total Segment Operating Income	$	111		$	96
	Corporate and Other Unallocated Expenses	(16		)	(17		)
	Other Unallocated Operating Income (Expense), net	(4		)	—
	Operating Income	91			79
	Equity Earnings from Timberland Venture	16			14
	Total Interest Expense, net	(34		)	(35		)
	Income before Income Taxes	$	73		$	58
		Nine Months Ended September 30,
		2013			2012
	Total Segment Operating Income	$	285		$	230
	Corporate and Other Unallocated Expenses	(51		)	(47		)
	Other Unallocated Operating Income (Expense), net	(3		)	1
	Operating Income	231			184
	Equity Earnings from Timberland Venture	47			42
	Total Interest Expense, net	(104		)	(104		)
	Income before Income Taxes	$	174		$	122
PLUM CREEK TIMBERLANDS L P [Member]	'
Segment Reporting Information [Line Items]	'
Schedule of Segment Reporting Information, by Segment [Table Text Block]	'
	The tables below present information about reported segments for the quarterly and nine-month periods ended September 30 (in millions):
		Northern			Southern			Real		Manufactured		Other (B)		Total (C)
		Resources (A)			Resources			Estate		Products
	Quarter Ended September 30, 2013
	External Revenues	$	60		$	111		$	96	$	94	$	5	$	366
	Intersegment Revenues	7			—			—		—		—		7
	Depreciation, Depletion and Amortization	11			17			1		4		1		34
	Basis of Real Estate Sold	—			—			27		—		—		27
	Other Operating Gain	—			—			—		—		1		1
	Operating Income	5			27			63		11		5		111
	Quarter Ended September 30, 2012
	External Revenues	$	58		$	110		$	96	$	85	$	5	$	354
	Intersegment Revenues	7			—			—		—		—		7
	Depreciation, Depletion and Amortization	7			19			—		4		—		30
	Basis of Real Estate Sold	—			—			36		—		—		36
	Other Operating Gain	—			—			—		—		—		—
	Operating Income	5			23			54		9		5		96
		Northern			Southern			Real		Manufactured		Other (B)		Total (C)
		Resources (A)			Resources			Estate		Products
	Nine Months Ended September 30, 2013
	External Revenues	$	174		$	313		$	227	$	279	$	16	$	1,009
	Intersegment Revenues	20			—			—		—		—		20
	Depreciation, Depletion and Amortization	23			45			1		12		2		83
	Basis of Real Estate Sold	—			—			69		—		—		69
	Other Operating Gain	—			—			—		—		1		1
	Operating Income	24			74			138		35		14		285
	Nine Months Ended September 30, 2012
	External Revenues	$	168		$	312		$	243	$	246	$	16	$	985
	Intersegment Revenues	17			—			—		—		—		17
	Depreciation, Depletion and Amortization	20			52			1		11		—		84
	Basis of Real Estate Sold	—			—			111		—		—		111
	Other Operating Gain	—			—			—		—		—		—
	Operating Income	15			66			113		22		14		230
	(A)	During the third quarter of 2013, the Northern Resources Segment recognized a loss of $4 million related to forest fires, which is included in depreciation, depletion and amortization in the consolidated financial statements.
	(B)	During the third quarter of 2013, the Operating Partnership sold certain mineral reserves for a gain of $1 million. This gain is reported as Other Operating Gain in our Other Segment and is included in Other Operating Income (Expense), net in the Consolidated Statements of Income.
	(C)	Consolidated depreciation, depletion and amortization includes unallocated corporate expense of $1 million for each of the quarterly periods ended September 30, 2013 and September 30, 2012; and $3 million for each of the nine-month periods ended September 30, 2013 and September 30, 2012.
Reconciliation of Total Segment Operating Income to Consolidated Income Before Income Taxes	'
	A reconciliation of total segment operating income to income before income taxes is presented below for the quarterly and nine-month periods ended September 30 (in millions):
		Quarter Ended September 30,
		2013			2012
	Total Segment Operating Income	$	111		$	96
	Corporate and Other Unallocated Expenses	(16		)	(17		)
	Other Unallocated Operating Income (Expense), net	(4		)	—
	Operating Income	91			79
	Equity Earnings from Timberland Venture	16			14
	Interest Expense, net	(20		)	(21		)
	Income before Income Taxes	$	87		$	72
		Nine Months Ended September 30,
		2013			2012
	Total Segment Operating Income	$	285		$	230
	Corporate and Other Unallocated Expenses	(51		)	(47		)
	Other Unallocated Operating Income (Expense), net	(3		)	1
	Operating Income	231			184
	Equity Earnings from Timberland Venture	47			42
	Interest Expense, net	(61		)	(61		)
	Income before Income Taxes	$	217		$	165

Basis_of_Presentation_Narrativ

Basis of Presentation (Narrative) (Details)	Sep. 30, 2013
	acre
PLUM CREEK TIMBER CO INC [Member]	'
Basis of Presentation [Line Items]	'
Timber and Timberlands, net (acres)	6,300,000
Product conversion facilities owned in the Northwest United States	7
Higher and better use timberlands, which are expected to be sold and/or developed, acres	800,000
Land Expect To Sell For Recreational Uses In Acres	600,000
Land Expect To Sell For Conservation In Acres	125,000
Land Designated With Development Potential In Acres	75,000
Total acres of non-strategic timberlands	300,000
PLUM CREEK TIMBERLANDS L P [Member]	'
Basis of Presentation [Line Items]	'
Percentage Of Ownership	100.00%
Timber and Timberlands, net (acres)	6,300,000
Product conversion facilities owned in the Northwest United States	7
Higher and better use timberlands, which are expected to be sold and/or developed, acres	800,000
Land Expect To Sell For Recreational Uses In Acres	600,000
Land Expect To Sell For Conservation In Acres	125,000
Land Designated With Development Potential In Acres	75,000
Total acres of non-strategic timberlands	300,000

Earnings_Per_Share_Schedule_of

Earnings Per Share (Schedule of Basic and Diluted Earnings Per Share) (Details) (USD $)	3 Months Ended		9 Months Ended
In Millions, except Per Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Earnings Per Share [Abstract]	'	'	'	'
Net Income Available to Common Stockholders	$72	$59	$174	$124
Denominator for Basic Earnings per Share	163	161.5	162.7	161.5
Effect of Dilutive Securities - Stock Options	0.3	0.3	0.4	0.3
Effect of Dilutive Securities - Restricted Stock Units and Value Management Plan	0.1	0.1	0.1	0
Denominator for Diluted Earnings per Share - Adjusted for Dilutive Securities	163.4	161.9	163.2	161.8
Net Income per Share-Basic	$0.44	$0.36	$1.06	$0.77
Net Income per Share-Diluted	$0.44	$0.36	$1.06	$0.76

Earnings_Per_Share_Schedule_of1

Earnings Per Share (Schedule of Antidilutive Options) (Details)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Earnings Per Share [Abstract]	'	'	'	'
Number of Options	0	1.1	0	1.1
Range of Exercise Prices	'N/A	'$41.55B toB $43.23	'N/A	'$41.55B toB $43.23
Expiration on or before	'N/A	'February 2021	'N/A	'February 2021

Inventories_Details

Inventories (Details) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
PLUM CREEK TIMBER CO INC [Member]	'	'
Inventory [Line Items]	'	'
Raw Materials (primarily logs)	$8	$9
Work-In-Process	2	2
Finished Goods	29	24
Total before Supplies	39	35
Supplies	14	14
Total	53	49
PLUM CREEK TIMBERLANDS L P [Member]	'	'
Inventory [Line Items]	'	'
Raw Materials (primarily logs)	8	9
Work-In-Process	2	2
Finished Goods	29	24
Total before Supplies	39	35
Supplies	14	14
Total	$53	$49

Timber_and_Timberlands_Timber_

Timber and Timberlands (Timber and Timberlands Table) (Details) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
PLUM CREEK TIMBER CO INC [Member]	'	'
Timber and Timberlands [Line Items]	'	'
Timber and Logging Roads, net	$2,162	$2,169
Timber Deeds, net	100	92
Timberlands	1,133	1,102
Timber and Timberlands, net	3,395	3,363
PLUM CREEK TIMBERLANDS L P [Member]	'	'
Timber and Timberlands [Line Items]	'	'
Timber and Logging Roads, net	2,162	2,169
Timber Deeds, net	100	92
Timberlands	1,133	1,102
Timber and Timberlands, net	$3,395	$3,363

Timber_and_Timberlands_Narrati

Timber and Timberlands (Narrative) (Details) (USD $)	3 Months Ended	9 Months Ended		12 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Dec. 31, 2011
		T			T
PLUM CREEK TIMBER CO INC [Member]	'	'	'	'	'
Total Payments to Acquire Timber Deeds Including Deposits	'	'	'	$103	'
Payments to Acquire Timber Deeds	'	18	98	'	5
Timber Deed Tons Purchased	'	900,000	'	'	4,700,000
Timber Deed Cutting Contract Term	'	'	'	'	'8 years
Timber Deed Cutting Contract Expiration Date	'	27-Jan-20	'	'	'
Loss from Catastrophes	4	4	'	'	'
PLUM CREEK TIMBERLANDS L P [Member]	'	'	'	'	'
Total Payments to Acquire Timber Deeds Including Deposits	'	'	'	103	'
Payments to Acquire Timber Deeds	'	18	98	'	5
Timber Deed Tons Purchased	'	900,000	'	'	4,700,000
Timber Deed Cutting Contract Term	'	'	'	'	'8 years
Timber Deed Cutting Contract Expiration Date	'	27-Jan-20	'	'	'
Loss from Catastrophes	$4	$4	'	'	'

Mineral_Rights_Narrative_Detai

Mineral Rights Narrative (Details) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
	T
PLUM CREEK TIMBER CO INC [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Finite-Lived Intangible Asset, Useful Life	'38 years	'
Aggregate Reserves Tons Purchased	255,000,000	'
Mineral Rights Acquired	$156	$0
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	4	'
Finite-Lived Intangible Assets, Amortization Expense, Year Two	4	'
Finite-Lived Intangible Assets, Amortization Expense, Year Three	4	'
Finite-Lived Intangible Assets, Amortization Expense, Year Four	4	'
Finite-Lived Intangible Assets, Amortization Expense, Year Five	4	'
PLUM CREEK TIMBERLANDS L P [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Finite-Lived Intangible Asset, Useful Life	'38 years	'
Aggregate Reserves Tons Purchased	255,000,000	'
Mineral Rights Acquired	156	0
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	4	'
Finite-Lived Intangible Assets, Amortization Expense, Year Two	4	'
Finite-Lived Intangible Assets, Amortization Expense, Year Three	4	'
Finite-Lived Intangible Assets, Amortization Expense, Year Four	4	'
Finite-Lived Intangible Assets, Amortization Expense, Year Five	$4	'

Property_Plant_and_Equipment_P

Property, Plant and Equipment (Property, Plant and Equipment Table) (Details) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
PLUM CREEK TIMBER CO INC [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Land, Buildings and Improvements	$88	$88
Machinery and Equipment	326	318
Property, Plant and Equipment, gross	414	406
Accumulated Depreciation	-296	-279
Property, Plant and Equipment, net	118	127
PLUM CREEK TIMBERLANDS L P [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Land, Buildings and Improvements	88	88
Machinery and Equipment	326	318
Property, Plant and Equipment, gross	414	406
Accumulated Depreciation	-296	-279
Property, Plant and Equipment, net	$118	$127

Income_Taxes_Narrative_Details

Income Taxes (Narrative) (Details) (USD $)	Sep. 30, 2013
In Millions, unless otherwise specified
PLUM CREEK TIMBER CO INC [Member]	'
Income Tax Examination [Line Items]	'
Tax Liability from Potential Adjustment	$100
Gain from Potential Tax Adjustment	600
Percentage of Gain Distributed in Common Stock	80.00%
PLUM CREEK TIMBERLANDS L P [Member]	'
Income Tax Examination [Line Items]	'
Tax Liability from Potential Adjustment	100
Gain from Potential Tax Adjustment	$600
Percentage of Gain Distributed in Common Stock	80.00%

Borrowings_Schedule_of_Debt_an

Borrowings (Schedule of Debt and Parenthetical Information) (Details) (USD $)

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

1 Months Ended

1 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

In Millions, unless otherwise specified

Dec. 31, 2013

Sep. 30, 2013

Sep. 30, 2012

Dec. 31, 2012

Dec. 31, 2008

Dec. 31, 2013

Sep. 30, 2013

Sep. 30, 2012

Dec. 31, 2012

Sep. 30, 2013

Dec. 31, 2012

Oct. 31, 2013

Sep. 30, 2013

Dec. 31, 2012

Oct. 31, 2013

Dec. 31, 2013

Sep. 30, 2013

Dec. 31, 2012

Dec. 31, 2013

Sep. 30, 2013

Dec. 31, 2012

PLUM CREEK TIMBER CO INC [Member]

PLUM CREEK TIMBER CO INC [Member]

PLUM CREEK TIMBER CO INC [Member]

PLUM CREEK TIMBER CO INC [Member]

PLUM CREEK TIMBER CO INC [Member]

PLUM CREEK TIMBERLANDS L P [Member]

PLUM CREEK TIMBERLANDS L P [Member]

PLUM CREEK TIMBERLANDS L P [Member]

PLUM CREEK TIMBERLANDS L P [Member]

Line of Credit [Member]

Line of Credit [Member]

Line of Credit [Member]

Line of Credit [Member]

Line of Credit [Member]

Line of Credit [Member]

Term Credit Agreement 1 [Member]

Term Credit Agreement 1 [Member]

Term Credit Agreement 1 [Member]

Term Credit Agreement 1 [Member]

Term Credit Agreement 1 [Member]

Term Credit Agreement 1 [Member]

PLUM CREEK TIMBER CO INC [Member]

PLUM CREEK TIMBER CO INC [Member]

PLUM CREEK TIMBER CO INC [Member]

PLUM CREEK TIMBERLANDS L P [Member]

PLUM CREEK TIMBERLANDS L P [Member]

PLUM CREEK TIMBERLANDS L P [Member]

PLUM CREEK TIMBER CO INC [Member]

PLUM CREEK TIMBER CO INC [Member]

PLUM CREEK TIMBER CO INC [Member]

PLUM CREEK TIMBERLANDS L P [Member]

PLUM CREEK TIMBERLANDS L P [Member]

PLUM CREEK TIMBERLANDS L P [Member]

Repayment of Debt [Member]

Repayment of Debt [Member]

Debt Instrument [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Senior Notes

'

$1,439

'

$1,613

'

'

$1,439

'

$1,613

'

'

'

'

'

'

'

'

'

'

'

'

Note Payable to Timberland Venture

'

783

'

783

783

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Long-term Debt

'

3,179

'

2,950

'

'

2,396

'

2,167

'

'

'

'

'

'

'

450

[1]

450

[1]

'

450

[1]

450

[1]

Current Portion of Long-Term Debt

'

74

'

248

'

'

74

'

248

'

'

'

'

'

'

'

'

'

'

'

'

Line of Credit

'

507

'

104

'

'

507

'

104

507

[2]

104

[2]

'

507

[2]

104

[2]

'

'

'

'

'

'

'

Letters of Credit Outstanding, Amount

'

'

'

'

'

'

'

'

'

1

'

'

1

'

'

'

'

'

'

'

'

Long Term Portion Of Total Borrowings

'

2,598

'

2,598

'

'

1,815

'

1,815

'

'

'

'

'

'

'

'

'

'

'

'

Term Credit Agreement, Interest

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1.68%

1.71%

'

1.68%

1.71%

Effective Interest Rate, Percentage

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1.00%

1.00%

'

1.00%

1.00%

Repayments of Long-term Debt

375

174

350

'

'

375

174

350

'

'

'

'

'

'

'

225

[1]

'

'

225

[1]

'

'

Debt Instrument, Maturity Date

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

3-Apr-19

'

'

3-Apr-19

'

Line of Credit, Remained Available

'

'

'

'

'

'

'

'

'

192

'

'

192

'

'

'

'

'

'

'

'

Line of Credit Capacity

'

'

'

'

'

'

'

'

'

700

'

'

700

'

'

'

'

'

'

'

'

Debt, Weighted Average Interest Rate

'

'

'

'

'

'

'

'

'

1.38%

1.43%

'

1.38%

1.43%

'

'

'

'

'

'

'

Line of Credit Facility, Decrease, Repayments

'

'

'

'

'

'

'

'

'

'

'

$355

'

'

$355

'

'

'

'

'

'

[1]

The company has a $450 million term credit agreement that matures on April 3, 2019. The interest rate on the $450 million term credit agreement was 1.68% and 1.71% as of SeptemberB 30, 2013 and DecemberB 31, 2012, respectively. After giving effect to expected patronage distributions, the effective net interest rate on the term loan was approximately 1% as of both SeptemberB 30, 2013 and DecemberB 31, 2012. On November 4, 2013, the company repaid $225 million of borrowings outstanding under the term credit agreement. See Note 16 of the Notes to Consolidated Financial Statements.

[2]

The weighted-average interest rate for the borrowings on the line of credit was 1.38% and 1.43% as of SeptemberB 30, 2013 and DecemberB 31, 2012, respectively. As of SeptemberB 30, 2013, we had $507 million of borrowings and $1 million of standby letters of credit outstanding; $192 million remained available for borrowing under our $700 million line of credit. As of OctoberB 1, 2013, $355 million of the borrowings outstanding under our line of credit was repaid.

Stockholders_Equity_Schedule_O

Stockholders' Equity (Schedule Of Components Of Stockholders Equity) (Details) (USD $)	3 Months Ended				9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'	'
Net Income	$72	'	'	$59	$174	$124
PLUM CREEK TIMBER CO INC [Member]	'	'	'	'	'	'
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'	'
Beginning Balance Shares	'	'	162	'	162	'
Beginning Balance	1,228	1,240	1,223	'	1,223	'
Net Income	72	46	56	59	174	124
Other Comprehensive Income (Loss), net of tax	0	2	3	2	5	5
Dividends	-72	-72	-68	'	'	'
Stock Option Exercises	'	10	25	'	'	'
Shares Issued under Stock Incentive Plans	'	'	0	'	'	'
Share-based Compensation	2	2	3	'	'	'
Common Stock Repurchased	'	'	-2	'	'	'
Ending Balance Shares	163	'	'	'	163	'
Ending Balance	1,230	1,228	1,240	'	1,230	'
Common Stock [Member] | PLUM CREEK TIMBER CO INC [Member]	'	'	'	'	'	'
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'	'
Beginning Balance Shares	'	162.7	162	'	162	'
Beginning Balance	'	2	2	'	2	'
Stock Option Exercises (in shares)	'	0.3	0.6	'	'	'
Stock Option Exercises	'	0	0	'	'	'
Shares Issued under Stock Incentive Plans (shares)	'	'	0.1	'	'	'
Shares Issued under Stock Incentive Plans	'	'	0	'	'	'
Stock Repurchased During Period, Shares	'	'	0	'	'	'
Common Stock Repurchased	'	'	0	'	'	'
Ending Balance Shares	163	163	162.7	'	163	'
Ending Balance	2	2	2	'	2	'
Paid-in Capital [Member] | PLUM CREEK TIMBER CO INC [Member]	'	'	'	'	'	'
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'	'
Beginning Balance	2,328	2,316	2,288	'	2,288	'
Stock Option Exercises	'	10	25	'	'	'
Shares Issued under Stock Incentive Plans	'	'	0	'	'	'
Share-based Compensation	2	2	3	'	'	'
Ending Balance	2,330	2,328	2,316	'	2,330	'
Retained Earnings (Accumulated Deficit) [Member] | PLUM CREEK TIMBER CO INC [Member]	'	'	'	'	'	'
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'	'
Beginning Balance	-135	-109	-97	'	-97	'
Net Income	72	46	56	'	'	'
Dividends	-72	-72	-68	'	'	'
Ending Balance	-135	-135	-109	'	-135	'
Treasury Stock [Member] | PLUM CREEK TIMBER CO INC [Member]	'	'	'	'	'	'
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'	'
Beginning Balance	'	'	-938	'	-938	'
Common Stock Repurchased	'	'	-2	'	'	'
Ending Balance	-940	-940	-940	'	-940	'
Accumulated Other Comprehensive Income (Loss) [Member] | PLUM CREEK TIMBER CO INC [Member]	'	'	'	'	'	'
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'	'
Beginning Balance	-27	-29	-32	'	-32	'
Other Comprehensive Income (Loss), net of tax	0	2	3	'	'	'
Ending Balance	($27)	($27)	($29)	'	($27)	'

Stockholders_Equity_Accumulate

Stockholders' Equity Accumulated Other Comprehensive Income (Details) (PLUM CREEK TIMBER CO INC [Member], USD $)	3 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012
Stockholders' Equity [Line Items]	'	'	'	'
Accumulated Other Comprehensive Income (Loss), Net of Tax	($27)	($27)	($29)	($32)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	-1	1	2	'
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	1	1	1	'
Accumulated Net Unrealized Investment Gain (Loss) [Member]	'	'	'	'
Stockholders' Equity [Line Items]	'	'	'	'
Accumulated Other Comprehensive Income (Loss), Net of Tax	10	11	10	8
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	-1	1	2	'
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0	0	0	'
Accumulated Defined Benefit Plans Adjustment [Member]	'	'	'	'
Stockholders' Equity [Line Items]	'	'	'	'
Accumulated Other Comprehensive Income (Loss), Net of Tax	-37	-38	-39	-40
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	0	0	0	'
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	$1	$1	$1	'

Stockholders_Equity_Reclassifi

Stockholders' Equity Reclassifications out of Accumulated Other Comprehensive Income (Loss) (Details) (Reclassification out of Accumulated Other Comprehensive Income [Member], Accumulated Defined Benefit Plans Adjustment [Member], PLUM CREEK TIMBER CO INC [Member], USD $)	3 Months Ended	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2013
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Defined Benefit Plans Adjustment [Member] | PLUM CREEK TIMBER CO INC [Member]	'	'
Stockholders' Equity [Line Items]	'	'
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI, Pension Benefit Plans, for Net Gain (Loss), before Tax	$1	$3
Income (Loss) from Continuing Operations	$1	$3

Partners_Capital_Schedule_Of_C

Partners' Capital (Schedule Of Components Of Partners' Capital) (Details) (PLUM CREEK TIMBERLANDS L P [Member], USD $)	3 Months Ended				9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Partners' Capital [Line Items]	'	'	'	'	'	'
Beginning Balances	$2,018	$2,030	$2,013	'	$2,013	'
Net Income before Allocation to Series T-1 Preferred Interest and Partners	86	61	70	73	217	167
Other Comprehensive Income (Loss), net of tax	0	2	3	2	5	5
Net Income Allocation to Series T-1 Preferred Interest	0	0	0	'	'	'
Distributions to Partners (Common Partnership Interests)	-72	-62	-45	'	'	'
Distributions for Series T-1 Preferred Interest	-14	-15	-14	'	'	'
Capital Contributions from Parent	2	2	3	'	'	'
Ending Balances	2,020	2,018	2,030	'	2,020	'
Preferred Partnership Interest [Member]	'	'	'	'	'	'
Partners' Capital [Line Items]	'	'	'	'	'	'
Beginning Balances	790	790	790	'	790	'
Net Income Allocation to Series T-1 Preferred Interest	14	15	14	'	'	'
Distributions for Series T-1 Preferred Interest	-14	-15	-14	'	'	'
Ending Balances	790	790	790	'	790	'
Common Partners' Capital [Member]	'	'	'	'	'	'
Partners' Capital [Line Items]	'	'	'	'	'	'
Beginning Balances	1,255	1,269	1,255	'	1,255	'
Net Income before Allocation to Series T-1 Preferred Interest and Partners	86	61	70	'	'	'
Net Income Allocation to Series T-1 Preferred Interest	-14	-15	-14	'	'	'
Distributions to Partners (Common Partnership Interests)	-72	-62	-45	'	'	'
Capital Contributions from Parent	2	2	3	'	'	'
Ending Balances	1,257	1,255	1,269	'	1,257	'
Accumulated Other Comprehensive Income (Loss) [Member]	'	'	'	'	'	'
Partners' Capital [Line Items]	'	'	'	'	'	'
Beginning Balances	-27	-29	-32	'	-32	'
Other Comprehensive Income (Loss), net of tax	0	2	3	'	'	'
Ending Balances	($27)	($27)	($29)	'	($27)	'

Partners_Capital_Accumulated_O

Partners' Capital Accumulated Other Comprehensive Income (Details) (PLUM CREEK TIMBERLANDS L P [Member], USD $)	3 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012
Partners' Capital [Line Items]	'	'	'	'
Accumulated Other Comprehensive Income (Loss), Net of Tax	($27)	($27)	($29)	($32)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	-1	1	2	'
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	1	1	1	'
Accumulated Defined Benefit Plans Adjustment [Member]	'	'	'	'
Partners' Capital [Line Items]	'	'	'	'
Accumulated Other Comprehensive Income (Loss), Net of Tax	-37	-38	-39	-40
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	0	0	0	'
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	1	1	1	'
Accumulated Net Unrealized Investment Gain (Loss) [Member]	'	'	'	'
Partners' Capital [Line Items]	'	'	'	'
Accumulated Other Comprehensive Income (Loss), Net of Tax	10	11	10	8
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	-1	1	2	'
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	$0	$0	$0	'

Partners_Capital_Reclassificat

Partners' Capital Reclassifications out of Accumulated Other Comprehensive Income (Loss) (Details) (PLUM CREEK TIMBERLANDS L P [Member], Reclassification out of Accumulated Other Comprehensive Income [Member], Accumulated Defined Benefit Plans Adjustment [Member], USD $)	3 Months Ended	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2013
PLUM CREEK TIMBERLANDS L P [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Defined Benefit Plans Adjustment [Member]	'	'
Partners' Capital [Line Items]	'	'
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI, Pension Benefit Plans, for Net Gain (Loss), before Tax	$1	$3
Income (Loss) from Continuing Operations	$1	$3

Fair_Value_Measurements_Level_

Fair Value Measurements (Level 1 Assets Reported in the Company's Financial Statements at Fair Value, Measured on a Recurring Basis) (Details) (USD $)	Sep. 30, 2013		Dec. 31, 2012		Sep. 30, 2012	Dec. 31, 2011
In Millions, unless otherwise specified
PLUM CREEK TIMBER CO INC [Member]	'		'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'	'
Cash and Cash Equivalents	$439		$356		$320	$254
Domestic Portion of Mutual Funds (percentage)	45.00%		'		'	'
International Portion of Mutual Funds (percentage)	25.00%		'		'	'
Debt Securities Portion of Mutual Funds (percentage)	30.00%		'		'	'
PLUM CREEK TIMBERLANDS L P [Member]	'		'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'	'
Cash and Cash Equivalents	439		356		320	254
Domestic Portion of Mutual Funds (percentage)	45.00%		'		'	'
International Portion of Mutual Funds (percentage)	25.00%		'		'	'
Debt Securities Portion of Mutual Funds (percentage)	30.00%		'		'	'
Fair Value, Measurements, Recurring [Member] | PLUM CREEK TIMBER CO INC [Member]	'		'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'	'
Cash Equivalents	434	[1]	354	[1]	'	'
Available-for-Sale Securities	37	[2]	34	[2]	'	'
Trading Securities	5	[2]	5	[2]	'	'
Investments, Fair Value Disclosure	476		393		'	'
Fair Value, Measurements, Recurring [Member] | PLUM CREEK TIMBERLANDS L P [Member]	'		'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'	'
Cash Equivalents	434	[1]	354	[1]	'	'
Available-for-Sale Securities	37	[2]	34	[2]	'	'
Trading Securities	5	[2]	5	[2]	'	'
Investments, Fair Value Disclosure	476		393		'	'
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | PLUM CREEK TIMBER CO INC [Member]	'		'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'	'
Cash Equivalents	434	[1]	354	[1]	'	'
Available-for-Sale Securities	37	[2]	34	[2]	'	'
Trading Securities	5	[2]	5	[2]	'	'
Investments, Fair Value Disclosure	476		393		'	'
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | PLUM CREEK TIMBERLANDS L P [Member]	'		'		'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'	'
Cash Equivalents	434	[1]	354	[1]	'	'
Available-for-Sale Securities	37	[2]	34	[2]	'	'
Trading Securities	5	[2]	5	[2]	'	'
Investments, Fair Value Disclosure	$476		$393		'	'
[1]	Consists of several money market funds and is included in the $439 million and $356 million of Cash and Cash Equivalents in the Consolidated Balance Sheets at SeptemberB 30, 2013 and DecemberB 31, 2012, respectively.
[2]	Consists of several mutual funds and is included in Investment in Grantor Trusts in the Consolidated Balance Sheets at SeptemberB 30, 2013 and DecemberB 31, 2012. At SeptemberB 30, 2013, investments in these mutual funds were approximately 45% in domestic (U.S.) equities, 25% in international equities and 30% in debt securities.

Fair_Value_Measurements_Narrat

Fair Value Measurements (Narrative) (Details) (Categories of Investments, Marketable Securities, Trading Securities [Member], USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
PLUM CREEK TIMBER CO INC [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Deferred Compensation Obligations Included in Other Liabilities	$5	$5
PLUM CREEK TIMBERLANDS L P [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Deferred Compensation Obligations Included in Other Liabilities	$5	$5

Fair_Value_Measurements_Fair_V

Fair Value Measurements Fair Value, Liabilities Measured on a Recurring Basis (Details) (USD $)	Sep. 30, 2013		Dec. 31, 2012		Dec. 31, 2008
PLUM CREEK TIMBER CO INC [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Senior Notes	$1,439,000,000		$1,613,000,000		'
Debt Instrument, Fair Value Disclosure	3,358,000,000		3,258,000,000		'
Line of Credit, Current	507,000,000		104,000,000		'
Note Payable to Timberland Venture	783,000,000		783,000,000		783,000,000
Long-term Debt	3,179,000,000		2,950,000,000		'
PLUM CREEK TIMBER CO INC [Member] | Fair Value, Inputs, Level 1 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	0		0		'
PLUM CREEK TIMBER CO INC [Member] | Fair Value, Inputs, Level 2 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	2,432,000,000		2,285,000,000		'
PLUM CREEK TIMBER CO INC [Member] | Fair Value, Inputs, Level 3 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	926,000,000		973,000,000		'
PLUM CREEK TIMBERLANDS L P [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Senior Notes	1,439,000,000		1,613,000,000		'
Debt Instrument, Fair Value Disclosure	2,432,000,000		2,285,000,000		'
Line of Credit, Current	507,000,000		104,000,000		'
Long-term Debt	2,396,000,000		2,167,000,000		'
PLUM CREEK TIMBERLANDS L P [Member] | Fair Value, Inputs, Level 1 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	0		0		'
PLUM CREEK TIMBERLANDS L P [Member] | Fair Value, Inputs, Level 2 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	2,432,000,000		2,285,000,000		'
PLUM CREEK TIMBERLANDS L P [Member] | Fair Value, Inputs, Level 3 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	0		0		'
Public Debt [Member] | PLUM CREEK TIMBER CO INC [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Senior Notes	1,353,000,000		1,353,000,000		'
Debt Instrument, Fair Value Disclosure	1,387,000,000		1,465,000,000		'
Public Debt [Member] | PLUM CREEK TIMBER CO INC [Member] | Fair Value, Inputs, Level 1 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	0		0		'
Public Debt [Member] | PLUM CREEK TIMBER CO INC [Member] | Fair Value, Inputs, Level 2 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	1,387,000,000		1,465,000,000		'
Public Debt [Member] | PLUM CREEK TIMBER CO INC [Member] | Fair Value, Inputs, Level 3 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	0		0		'
Public Debt [Member] | PLUM CREEK TIMBERLANDS L P [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	1,387,000,000		1,465,000,000		'
Senior Notes Short And Long Term	1,353,000,000		1,353,000,000		'
Public Debt [Member] | PLUM CREEK TIMBERLANDS L P [Member] | Fair Value, Inputs, Level 1 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	0		0		'
Public Debt [Member] | PLUM CREEK TIMBERLANDS L P [Member] | Fair Value, Inputs, Level 2 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	1,387,000,000		1,465,000,000		'
Public Debt [Member] | PLUM CREEK TIMBERLANDS L P [Member] | Fair Value, Inputs, Level 3 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	0		0		'
Private Debt [Member] | PLUM CREEK TIMBER CO INC [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Senior Notes	86,000,000		260,000,000		'
Debt Instrument, Fair Value Disclosure	88,000,000		266,000,000		'
Private Debt [Member] | PLUM CREEK TIMBER CO INC [Member] | Fair Value, Inputs, Level 1 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	0		0		'
Private Debt [Member] | PLUM CREEK TIMBER CO INC [Member] | Fair Value, Inputs, Level 2 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	88,000,000		266,000,000		'
Private Debt [Member] | PLUM CREEK TIMBER CO INC [Member] | Fair Value, Inputs, Level 3 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	0		0		'
Private Debt [Member] | PLUM CREEK TIMBERLANDS L P [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	88,000,000		266,000,000		'
Senior Notes Short And Long Term	86,000,000		260,000,000		'
Private Debt [Member] | PLUM CREEK TIMBERLANDS L P [Member] | Fair Value, Inputs, Level 1 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	0		0		'
Private Debt [Member] | PLUM CREEK TIMBERLANDS L P [Member] | Fair Value, Inputs, Level 2 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	88,000,000		266,000,000		'
Private Debt [Member] | PLUM CREEK TIMBERLANDS L P [Member] | Fair Value, Inputs, Level 3 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	0		0		'
Note Payable to Timberland Venture [Member] | PLUM CREEK TIMBER CO INC [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	926,000,000		973,000,000		'
Note Payable to Timberland Venture	783,000,000		783,000,000		'
Note Payable to Timberland Venture [Member] | PLUM CREEK TIMBER CO INC [Member] | Fair Value, Inputs, Level 1 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	0		0		'
Note Payable to Timberland Venture [Member] | PLUM CREEK TIMBER CO INC [Member] | Fair Value, Inputs, Level 2 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	0		0		'
Note Payable to Timberland Venture [Member] | PLUM CREEK TIMBER CO INC [Member] | Fair Value, Inputs, Level 3 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	926,000,000		973,000,000		'
Term Credit Agreement 1 [Member] | PLUM CREEK TIMBER CO INC [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	450,000,000		450,000,000		'
Long-term Debt	450,000,000	[1]	450,000,000	[1]	'
Term Credit Agreement 1 [Member] | PLUM CREEK TIMBER CO INC [Member] | Fair Value, Inputs, Level 1 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	0		0		'
Term Credit Agreement 1 [Member] | PLUM CREEK TIMBER CO INC [Member] | Fair Value, Inputs, Level 2 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	450,000,000		450,000,000		'
Term Credit Agreement 1 [Member] | PLUM CREEK TIMBER CO INC [Member] | Fair Value, Inputs, Level 3 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	0		0		'
Term Credit Agreement 1 [Member] | PLUM CREEK TIMBERLANDS L P [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	450,000,000		450,000,000		'
Long-term Debt	450,000,000	[1]	450,000,000	[1]	'
Term Credit Agreement 1 [Member] | PLUM CREEK TIMBERLANDS L P [Member] | Fair Value, Inputs, Level 1 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	0		0		'
Term Credit Agreement 1 [Member] | PLUM CREEK TIMBERLANDS L P [Member] | Fair Value, Inputs, Level 2 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	450,000,000		450,000,000		'
Term Credit Agreement 1 [Member] | PLUM CREEK TIMBERLANDS L P [Member] | Fair Value, Inputs, Level 3 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Debt Instrument, Fair Value Disclosure	0		0		'
Line of Credit [Member] | PLUM CREEK TIMBER CO INC [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Line of Credit, Current	507,000,000		104,000,000		'
Lines of Credit, Fair Value Disclosure	507,000,000		104,000,000		'
Line of Credit [Member] | PLUM CREEK TIMBER CO INC [Member] | Fair Value, Inputs, Level 1 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Lines of Credit, Fair Value Disclosure	0		0		'
Line of Credit [Member] | PLUM CREEK TIMBER CO INC [Member] | Fair Value, Inputs, Level 2 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Lines of Credit, Fair Value Disclosure	507,000,000		104,000,000		'
Line of Credit [Member] | PLUM CREEK TIMBER CO INC [Member] | Fair Value, Inputs, Level 3 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Lines of Credit, Fair Value Disclosure	0		0		'
Line of Credit [Member] | PLUM CREEK TIMBERLANDS L P [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Line of Credit, Current	507,000,000		104,000,000		'
Lines of Credit, Fair Value Disclosure	507,000,000		104,000,000		'
Line of Credit [Member] | PLUM CREEK TIMBERLANDS L P [Member] | Fair Value, Inputs, Level 1 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Lines of Credit, Fair Value Disclosure	0		0		'
Line of Credit [Member] | PLUM CREEK TIMBERLANDS L P [Member] | Fair Value, Inputs, Level 2 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Lines of Credit, Fair Value Disclosure	507,000,000		104,000,000		'
Line of Credit [Member] | PLUM CREEK TIMBERLANDS L P [Member] | Fair Value, Inputs, Level 3 [Member]	'		'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'		'
Lines of Credit, Fair Value Disclosure	$0		$0		'
[1]	The company has a $450 million term credit agreement that matures on April 3, 2019. The interest rate on the $450 million term credit agreement was 1.68% and 1.71% as of SeptemberB 30, 2013 and DecemberB 31, 2012, respectively. After giving effect to expected patronage distributions, the effective net interest rate on the term loan was approximately 1% as of both SeptemberB 30, 2013 and DecemberB 31, 2012. On November 4, 2013, the company repaid $225 million of borrowings outstanding under the term credit agreement. See Note 16 of the Notes to Consolidated Financial Statements.

Employee_Pension_Plans_Compone

Employee Pension Plans (Component of Pension Cost Recognized in Net Income) (Details) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
PLUM CREEK TIMBER CO INC [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Service Cost	$2	$2	$6	$6
Interest Cost	2	2	6	6
Expected Return on Plan Assets	-2	-2	-6	-6
Amortization of (Gains) Losses	1	1	3	3
Total Pension Cost	3	3	9	9
PLUM CREEK TIMBERLANDS L P [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Service Cost	2	2	6	6
Interest Cost	2	2	6	6
Expected Return on Plan Assets	-2	-2	-6	-6
Amortization of (Gains) Losses	1	1	3	3
Total Pension Cost	$3	$3	$9	$9

Employee_Pension_Plans_Narrati

Employee Pension Plans Narrative (Details) (USD $)	Sep. 30, 2013
PLUM CREEK TIMBER CO INC [Member]	'
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]	'
Expected Defined Benefit Plan Contribution To Qualified Pension Plan Minimum Range In Next Fiscal Year	$0
Expected Defined Benefit Plan Contribution To Qualified Pension Plan Maximum Range In Next Fiscal Year	10,000,000
Defined Benefit Plan Contribution To Non-Qualified Pension Plan Minimum Range in Current Fiscal Year	0
Defined Benefit Plan Contribution To Non-Qualified Pension Plan Maximum Range in Current Fiscal Year	2,000,000
PLUM CREEK TIMBERLANDS L P [Member]	'
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]	'
Expected Defined Benefit Plan Contribution To Qualified Pension Plan Minimum Range In Next Fiscal Year	0
Expected Defined Benefit Plan Contribution To Qualified Pension Plan Maximum Range In Next Fiscal Year	10,000,000
Defined Benefit Plan Contribution To Non-Qualified Pension Plan Minimum Range in Current Fiscal Year	0
Defined Benefit Plan Contribution To Non-Qualified Pension Plan Maximum Range in Current Fiscal Year	$2,000,000

Variable_Interest_Entities_Det

Variable Interest Entities (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2008	Sep. 30, 2013	Dec. 31, 2012
PLUM CREEK TIMBER CO INC [Member]	'	'	'
Variable Interest Entity [Line Items]	'	'	'
Amount borrowed from the Timberland Venture	$783	$783	$783
Equity Investment in Timberland Venture	'	195	204
PLUM CREEK TIMBERLANDS L P [Member]	'	'	'
Variable Interest Entity [Line Items]	'	'	'
Proceeds from Partnership Contribution	783	'	'
Equity Investment in Timberland Venture	'	195	204
PC Ventures [Member]	'	'	'
Variable Interest Entity [Line Items]	'	'	'
Amount borrowed from the Timberland Venture	783	'	'
Variable Interest Entity, Not Primary Beneficiary [Member] | PLUM CREEK TIMBER CO INC [Member]	'	'	'
Variable Interest Entity [Line Items]	'	'	'
Maximum exposure to loss	'	195	'
Variable Interest Entity, Not Primary Beneficiary [Member] | PLUM CREEK TIMBERLANDS L P [Member]	'	'	'
Variable Interest Entity [Line Items]	'	'	'
Maximum exposure to loss	'	195	'
Timberland Venture [Member] | PLUM CREEK TIMBER CO INC [Member]	'	'	'
Variable Interest Entity [Line Items]	'	'	'
Contributed Acres of Timberlands to Venture	454,000	'	'
Preferred interest in venture	705	'	'
Common Interest in Venture (Percent)	9.00%	'	'
Common interest in venture	78	'	'
Proceeds from Partnership Contribution	783	'	'
Other Partnership Ownership Percentage	91.00%	'	'
Total Common Interests in Venture	'	861	'
Timberland Venture [Member] | PLUM CREEK TIMBERLANDS L P [Member]	'	'	'
Variable Interest Entity [Line Items]	'	'	'
Contributed Acres of Timberlands to Venture	454,000	'	'
Preferred interest in venture	705	'	'
Common Interest in Venture (Percent)	9.00%	'	'
Common interest in venture	78	'	'
Proceeds from Partnership Contribution	783	'	'
Other Partnership Ownership Percentage	91.00%	'	'
Total Common Interests in Venture	'	$861	'

Summarized_Income_Statement_In2

Summarized Income Statement Information of Unconsolidated Subsidiary (Details) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013		Sep. 30, 2012
PLUM CREEK TIMBER CO INC [Member]	'	'	'		'
Schedule of Equity Method Investments [Line Items]	'	'	'		'
Equity Earnings from Timberland Venture	$16	$14	$47		$42
Amortization of Basis Difference	'	'	7		6
Interest Expense, Related Party	14	14	43		43
Revenues	'	'	13		10
Cost of Goods Sold	'	'	12	[1]	11	[1]
Selling, General and Administrative Expenses	'	'	4		6
Operating Income (Loss)	'	'	-3		-7
Interest Income, net	'	'	43		43
Net Income before Allocation to Preferred and Common Interests	'	'	40		36
Depreciation, Depletion and Amortization included in Cost of Goods Sold	'	'	11		10
PLUM CREEK TIMBERLANDS L P [Member]	'	'	'		'
Schedule of Equity Method Investments [Line Items]	'	'	'		'
Equity Earnings from Timberland Venture	16	14	47		42
Amortization of Basis Difference	'	'	7		6
Revenues	'	'	13		10
Cost of Goods Sold	'	'	12	[1]	11	[1]
Selling, General and Administrative Expenses	'	'	4		6
Operating Income (Loss)	'	'	-3		-7
Interest Income, net	'	'	43		43
Net Income before Allocation to Preferred and Common Interests	'	'	40		36
Depreciation, Depletion and Amortization included in Cost of Goods Sold	'	'	$11		$10
[1]	Cost of Goods Sold includes Depreciation, Depletion and Amortization of $11 million and $10 million for the nine-month periods ended SeptemberB 30, 2013 and 2012, respectively.

Segment_Information_Narrative_

Segment Information (Narrative) (Details) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
PLUM CREEK TIMBER CO INC [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Loss from Catastrophes	$4	'	$4	'
Unallocated corporate depreciation	1	1	3	3
Gain (Loss) on Sale of Minerals	1	'	1	'
PLUM CREEK TIMBERLANDS L P [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Loss from Catastrophes	4	'	4	'
Unallocated corporate depreciation	1	1	3	3
Gain (Loss) on Sale of Minerals	$1	'	$1	'

Segment_Information_Summary_of

Segment Information (Summary of Reported Segments) (Details) (USD $)	3 Months Ended				9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012
PLUM CREEK TIMBER CO INC [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Depreciation, Depletion and Amortization	'		'		$86		$87
Operating Income	91		79		231		184
PLUM CREEK TIMBER CO INC [Member] | Northern Resources [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
External Revenues	60	[1]	58	[1]	174	[1]	168	[1]
Intersegment Revenues	7	[1]	7	[1]	20	[1]	17	[1]
Depreciation, Depletion and Amortization	11	[1]	7	[1]	23	[1]	20	[1]
Basis of Real Estate Sold	0	[1]	0	[1]	0	[1]	0	[1]
Other Operating Income	0	[1]	0	[1]	0	[1]	0	[1]
Operating Income	5	[1]	5	[1]	24	[1]	15	[1]
PLUM CREEK TIMBER CO INC [Member] | Southern Resources [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
External Revenues	111		110		313		312
Intersegment Revenues	0		0		0		0
Depreciation, Depletion and Amortization	17		19		45		52
Basis of Real Estate Sold	0		0		0		0
Other Operating Income	0		0		0		0
Operating Income	27		23		74		66
PLUM CREEK TIMBER CO INC [Member] | Real Estate [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
External Revenues	96		96		227		243
Intersegment Revenues	0		0		0		0
Depreciation, Depletion and Amortization	1		0		1		1
Basis of Real Estate Sold	27		36		69		111
Other Operating Income	0		0		0		0
Operating Income	63		54		138		113
PLUM CREEK TIMBER CO INC [Member] | Manufactured Products [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
External Revenues	94		85		279		246
Intersegment Revenues	0		0		0		0
Depreciation, Depletion and Amortization	4		4		12		11
Basis of Real Estate Sold	0		0		0		0
Other Operating Income	0		0		0		0
Operating Income	11		9		35		22
PLUM CREEK TIMBER CO INC [Member] | Other Segment [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
External Revenues	5	[2]	5	[2]	16	[2]	16	[2]
Intersegment Revenues	0	[2]	0	[2]	0	[2]	0	[2]
Depreciation, Depletion and Amortization	1	[2]	0	[2]	2	[2]	0	[2]
Basis of Real Estate Sold	0	[2]	0	[2]	0	[2]	0	[2]
Other Operating Income	1	[2]	0	[2]	1	[2]	0	[2]
Operating Income	5	[2]	5	[2]	14	[2]	14	[2]
PLUM CREEK TIMBER CO INC [Member] | Operating Segments [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
External Revenues	366	[3]	354	[3]	1,009	[3]	985	[3]
Intersegment Revenues	7	[3]	7	[3]	20	[3]	17	[3]
Depreciation, Depletion and Amortization	34	[3]	30	[3]	83	[3]	84	[3]
Basis of Real Estate Sold	27	[3]	36	[3]	69	[3]	111	[3]
Other Operating Income	1	[3]	0	[3]	1	[3]	0	[3]
Operating Income	111	[3]	96	[3]	285	[3]	230	[3]
PLUM CREEK TIMBERLANDS L P [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Depreciation, Depletion and Amortization	'		'		86		87
Operating Income	91		79		231		184
PLUM CREEK TIMBERLANDS L P [Member] | Northern Resources [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
External Revenues	60	[1]	58	[1]	174	[1]	168	[1]
Intersegment Revenues	7	[1]	7	[1]	20	[1]	17	[1]
Depreciation, Depletion and Amortization	11	[1]	7	[1]	23	[1]	20	[1]
Basis of Real Estate Sold	0	[1]	0	[1]	0	[1]	0	[1]
Other Operating Income	0	[1]	0	[1]	0	[1]	0	[1]
Operating Income	5	[1]	5	[1]	24	[1]	15	[1]
PLUM CREEK TIMBERLANDS L P [Member] | Southern Resources [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
External Revenues	111		110		313		312
Intersegment Revenues	0		0		0		0
Depreciation, Depletion and Amortization	17		19		45		52
Basis of Real Estate Sold	0		0		0		0
Other Operating Income	0		0		0		0
Operating Income	27		23		74		66
PLUM CREEK TIMBERLANDS L P [Member] | Real Estate [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
External Revenues	96		96		227		243
Intersegment Revenues	0		0		0		0
Depreciation, Depletion and Amortization	1		0		1		1
Basis of Real Estate Sold	27		36		69		111
Other Operating Income	0		0		0		0
Operating Income	63		54		138		113
PLUM CREEK TIMBERLANDS L P [Member] | Manufactured Products [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
External Revenues	94		85		279		246
Intersegment Revenues	0		0		0		0
Depreciation, Depletion and Amortization	4		4		12		11
Basis of Real Estate Sold	0		0		0		0
Other Operating Income	0		0		0		0
Operating Income	11		9		35		22
PLUM CREEK TIMBERLANDS L P [Member] | Other Segment [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
External Revenues	5	[4]	5	[4]	16	[4]	16	[4]
Intersegment Revenues	0	[4]	0	[4]	0	[4]	0	[4]
Depreciation, Depletion and Amortization	1	[4]	0	[4]	2	[4]	0	[4]
Basis of Real Estate Sold	0	[4]	0	[4]	0	[4]	0	[4]
Other Operating Income	1	[4]	0	[4]	1	[4]	0	[4]
Operating Income	5	[4]	5	[4]	14	[4]	14	[4]
PLUM CREEK TIMBERLANDS L P [Member] | Operating Segments [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
External Revenues	366	[3]	354	[3]	1,009	[3]	985	[3]
Intersegment Revenues	7	[3]	7	[3]	20	[3]	17	[3]
Depreciation, Depletion and Amortization	34	[3]	30	[3]	83	[3]	84	[3]
Basis of Real Estate Sold	27	[3]	36	[3]	69	[3]	111	[3]
Other Operating Income	1	[3]	0	[3]	1	[3]	0	[3]
Operating Income	$111	[3]	$96	[3]	$285	[3]	$230	[3]
[1]	During the third quarter of 2013, the Northern Resources Segment recognized a loss of $4 million related to forest fires, which is included in depreciation, depletion and amortization in the consolidated financial statements.
[2]	During the third quarter of 2013, the company sold certain mineral reserves for a gain of $1 million. This gain is reported as Other Operating Gain in our Other Segment and is included in Other Operating Income (Expense), net in the Consolidated Statements of Income.
[3]	Consolidated depreciation, depletion and amortization includes unallocated corporate expense of $1 million for each of the quarterly periods ended SeptemberB 30, 2013 and SeptemberB 30, 2012; and $3 million for each of the nine-month periods ended SeptemberB 30, 2013 and SeptemberB 30, 2012.
[4]	During the third quarter of 2013, the Operating Partnership sold certain mineral reserves for a gain of $1 million. This gain is reported as Other Operating Gain in our Other Segment and is included in Other Operating Income (Expense), net in the Consolidated Statements of Income.

Segment_Information_Reconcilia

Segment Information (Reconciliation of Total Segment Operating Income to Consolidated Income Before Income Taxes) (Details) (USD $)	3 Months Ended				9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012
PLUM CREEK TIMBER CO INC [Member]	'		'		'		'
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]	'		'		'		'
Operating Income	$91		$79		$231		$184
Equity Earnings from Timberland Venture	16		14		47		42
Total Interest Expense, net	-34		-35		-104		-104
Income before Income Taxes	73		58		174		122
PLUM CREEK TIMBER CO INC [Member] | Operating Segments [Member]	'		'		'		'
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]	'		'		'		'
Operating Income	111	[1]	96	[1]	285	[1]	230	[1]
PLUM CREEK TIMBER CO INC [Member] | Unallocated Amount to Segment [Member]	'		'		'		'
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]	'		'		'		'
Operating Income	-16		-17		-51		-47
PLUM CREEK TIMBER CO INC [Member] | Other Unallocated Operating Income Expense Net [Member]	'		'		'		'
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]	'		'		'		'
Operating Income	-4		0		-3		1
PLUM CREEK TIMBERLANDS L P [Member]	'		'		'		'
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]	'		'		'		'
Operating Income	91		79		231		184
Equity Earnings from Timberland Venture	16		14		47		42
Total Interest Expense, net	-20		-21		-61		-61
Income before Income Taxes	87		72		217		165
PLUM CREEK TIMBERLANDS L P [Member] | Operating Segments [Member]	'		'		'		'
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]	'		'		'		'
Operating Income	111	[1]	96	[1]	285	[1]	230	[1]
PLUM CREEK TIMBERLANDS L P [Member] | Unallocated Amount to Segment [Member]	'		'		'		'
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]	'		'		'		'
Operating Income	-16		-17		-51		-47
PLUM CREEK TIMBERLANDS L P [Member] | Other Unallocated Operating Income Expense Net [Member]	'		'		'		'
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]	'		'		'		'
Operating Income	($4)		$0		($3)		$1
[1]	Consolidated depreciation, depletion and amortization includes unallocated corporate expense of $1 million for each of the quarterly periods ended SeptemberB 30, 2013 and SeptemberB 30, 2012; and $3 million for each of the nine-month periods ended SeptemberB 30, 2013 and SeptemberB 30, 2012.

Subsequent_Events_Details

Subsequent Events (Details) (Dividend Declared [Member], PLUM CREEK TIMBER CO INC [Member], USD $)	9 Months Ended
In Millions, except Per Share data, unless otherwise specified	Sep. 30, 2013	Nov. 05, 2013
Dividend Declared [Member] | PLUM CREEK TIMBER CO INC [Member]	'	'
Dividends Payable [Line Items]	'	'
Dividends Payable, Date Declared, Day, Month and Year	5-Nov-13	'
Dividend Payment per Share	'	$0.44
Dividend Payment, Approximately	'	$78
Dividends Payable, Date to be Paid, Day, Month and Year	27-Nov-13	'
Stockholders of Record Date	15-Nov-13	'

Subsequent_Events_Acquisition_

Subsequent Events Acquisition (Details) (USD $)	3 Months Ended		9 Months Ended
	Dec. 31, 2013		Sep. 30, 2013	Sep. 30, 2012	Oct. 28, 2013
			acre
PLUM CREEK TIMBER CO INC [Member]	'		'	'	'
Schedule of Pending Business Acquisitions [Line Items]	'		'	'	'
Timber And Timberlands Acres Owned	'		6,300,000	'	'
Land Designated With Development Potential In Acres	'		75,000	'	'
Business Acquisition, Cost of Acquired Entity, Purchase Price	'		'	'	$1,100,000,000
Business Acquisition, Cost of Acquired Entity, Cash Paid	'		'	'	226,000,000
Installment Note Payable	'		'	'	860,000,000
Stock Issued During Period, Shares, New Issues	13,915,000		'	'	'
Stock Issued During Period, Value, New Issues	606,000,000		'	'	'
Repayments of Long-term Debt	375,000,000		174,000,000	350,000,000	'
PLUM CREEK TIMBERLANDS L P [Member]	'		'	'	'
Schedule of Pending Business Acquisitions [Line Items]	'		'	'	'
Timber And Timberlands Acres Owned	'		6,300,000	'	'
Land Designated With Development Potential In Acres	'		75,000	'	'
Business Acquisition, Cost of Acquired Entity, Purchase Price	'		'	'	1,100,000,000
Business Acquisition, Cost of Acquired Entity, Cash Paid	'		'	'	226,000,000
Installment Note Payable	'		'	'	860,000,000
Repayments of Long-term Debt	375,000,000		174,000,000	350,000,000	'
Pending Business Acquisition [Member] | PLUM CREEK TIMBER CO INC [Member]	'		'	'	'
Schedule of Pending Business Acquisitions [Line Items]	'		'	'	'
Timber And Timberlands Acres Owned	'		'	'	501,000
Land Designated With Development Potential In Acres	'		'	'	109,000
Pending Business Acquisition [Member] | PLUM CREEK TIMBERLANDS L P [Member]	'		'	'	'
Schedule of Pending Business Acquisitions [Line Items]	'		'	'	'
Timber And Timberlands Acres Owned	'		'	'	501,000
Land Designated With Development Potential In Acres	'		'	'	109,000
JV2 [Member] | PLUM CREEK TIMBER CO INC [Member]	'		'	'	'
Schedule of Pending Business Acquisitions [Line Items]	'		'	'	'
Land Designated With Development Potential In Acres	'		'	'	87,000
Equity Method Investment, Ownership Percentage	'		'	'	50.00%
JV2 [Member] | PLUM CREEK TIMBERLANDS L P [Member]	'		'	'	'
Schedule of Pending Business Acquisitions [Line Items]	'		'	'	'
Land Designated With Development Potential In Acres	'		'	'	87,000
Equity Method Investment, Ownership Percentage	'		'	'	50.00%
JV1 [Member] | PLUM CREEK TIMBER CO INC [Member]	'		'	'	'
Schedule of Pending Business Acquisitions [Line Items]	'		'	'	'
Land Designated With Development Potential In Acres	'		'	'	22,000
Equity Method Investment, Ownership Percentage	'		'	'	5.00%
JV1 [Member] | PLUM CREEK TIMBERLANDS L P [Member]	'		'	'	'
Schedule of Pending Business Acquisitions [Line Items]	'		'	'	'
Land Designated With Development Potential In Acres	'		'	'	22,000
Equity Method Investment, Ownership Percentage	'		'	'	5.00%
Term Credit Agreement 1 [Member] | PLUM CREEK TIMBER CO INC [Member]	'		'	'	'
Schedule of Pending Business Acquisitions [Line Items]	'		'	'	'
Repayments of Long-term Debt	225,000,000	[1]	'	'	'
Term Credit Agreement 1 [Member] | PLUM CREEK TIMBERLANDS L P [Member]	'		'	'	'
Schedule of Pending Business Acquisitions [Line Items]	'		'	'	'
Repayments of Long-term Debt	$225,000,000	[1]	'	'	'
[1]	The company has a $450 million term credit agreement that matures on April 3, 2019. The interest rate on the $450 million term credit agreement was 1.68% and 1.71% as of SeptemberB 30, 2013 and DecemberB 31, 2012, respectively. After giving effect to expected patronage distributions, the effective net interest rate on the term loan was approximately 1% as of both SeptemberB 30, 2013 and DecemberB 31, 2012. On November 4, 2013, the company repaid $225 million of borrowings outstanding under the term credit agreement. See Note 16 of the Notes to Consolidated Financial Statements.

Supplemental_Disclosures_Detai

Supplemental Disclosures (Details) (PLUM CREEK TIMBERLANDS L P [Member], USD $)	Sep. 30, 2013
In Millions, unless otherwise specified
PLUM CREEK TIMBERLANDS L P [Member]	'
Supplemental Disclosures [Line Items]	'
Senior Notes Short and Long Term Aggregate	$1,358