Segment Information (Summary of Reported Segments) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013
PLUM CREEK TIMBER CO INC [Member]
Segment Reporting Information [Line Items]
External Revenues	$ 356		$ 303		$ 673		$ 643
Depreciation, Depletion and Amortization					66		51
Basis of Real Estate Sold					31		42
Earnings from Unconsolidated Entities	15		17		29		31
Operating Income (Loss)	82		62		139		140
PLUM CREEK TIMBER CO INC [Member] | Northern Resources [Member]
Segment Reporting Information [Line Items]
External Revenues	44		48		113		114
Intersegment Revenues	6		5		14		13
Depreciation, Depletion and Amortization	6		5		14		12
Basis of Real Estate Sold	0		0		0		0
Other Operating Gain (Loss)	0		0		0		0
Operating Income (Loss)	5		8		21		19
PLUM CREEK TIMBER CO INC [Member] | Southern Resources [Member]
Segment Reporting Information [Line Items]
External Revenues	127		98		250		202
Intersegment Revenues	0		0		0		0
Depreciation, Depletion and Amortization	19		14		37		28
Basis of Real Estate Sold	0		0		0		0
Other Operating Gain (Loss)	0		0		0		0
Operating Income (Loss)	33		23		64		47
PLUM CREEK TIMBER CO INC [Member] | Real Estate [Member]
Segment Reporting Information [Line Items]
External Revenues	77		53		100		131
Intersegment Revenues	0		0		0		0
Depreciation, Depletion and Amortization	0		0		0		0
Basis of Real Estate Sold	25		17		31		42
Other Operating Gain (Loss)	0		0		0		0
Operating Income (Loss)	45		30		57		75
PLUM CREEK TIMBER CO INC [Member] | Manufacturing [Member]
Segment Reporting Information [Line Items]
External Revenues	94	[1]	99	[1]	184	[1]	185	[1]
Intersegment Revenues	0	[1]	0	[1]	0	[1]	0	[1]
Depreciation, Depletion and Amortization	6	[1]	4	[1]	9	[1]	8	[1]
Basis of Real Estate Sold	0	[1]	0	[1]	0	[1]	0	[1]
Other Operating Gain (Loss)	2	[1]	0	[1]	2	[1]	0	[1]
Operating Income (Loss)	10	[1]	14	[1]	19	[1]	24	[1]
PLUM CREEK TIMBER CO INC [Member] | Energy and Natural Resources [Member]
Segment Reporting Information [Line Items]
External Revenues	9		5		18		11
Intersegment Revenues	0		0		0		0
Depreciation, Depletion and Amortization	2		1		4		1
Basis of Real Estate Sold	0		0		0		0
Other Operating Gain (Loss)	0		0		0		0
Operating Income (Loss)	6		4		12		9
PLUM CREEK TIMBER CO INC [Member] | Other Segment [Member]
Segment Reporting Information [Line Items]
External Revenues	5	[2]	0	[2]	8	[2]	0	[2]
Intersegment Revenues	0	[2]	0	[2]	0	[2]	0	[2]
Depreciation, Depletion and Amortization	0	[2]	0	[2]	0	[2]	0	[2]
Basis of Real Estate Sold	0	[2]	0	[2]	0	[2]	0	[2]
Other Operating Gain (Loss)	0	[2]	0	[2]	0	[2]	0	[2]
Operating Income (Loss)	(3)	[2]	0	[2]	(4)	[2]	0	[2]
PLUM CREEK TIMBER CO INC [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
External Revenues	356	[3]	303	[3]	673	[3]	643	[3]
Intersegment Revenues	6	[3]	5	[3]	14	[3]	13	[3]
Depreciation, Depletion and Amortization	33	[3]	24	[3]	64	[3]	49	[3]
Basis of Real Estate Sold	25	[3]	17	[3]	31	[3]	42	[3]
Other Operating Gain (Loss)	2	[3]	0	[3]	2	[3]	0	[3]
Operating Income (Loss)	96	[3]	79	[3]	169	[3]	174	[3]
PLUM CREEK TIMBERLANDS L P [Member]
Segment Reporting Information [Line Items]
External Revenues	356		303		673		643
Depreciation, Depletion and Amortization					66		51
Basis of Real Estate Sold					31		42
Earnings from Unconsolidated Entities	15		17		29		31
Operating Income (Loss)	82		62		139		140
PLUM CREEK TIMBERLANDS L P [Member] | Northern Resources [Member]
Segment Reporting Information [Line Items]
External Revenues	44		48		113		114
Intersegment Revenues	6		5		14		13
Depreciation, Depletion and Amortization	6		5		14		12
Basis of Real Estate Sold	0		0		0		0
Other Operating Gain (Loss)	0		0		0		0
Operating Income (Loss)	5		8		21		19
PLUM CREEK TIMBERLANDS L P [Member] | Southern Resources [Member]
Segment Reporting Information [Line Items]
External Revenues	127		98		250		202
Intersegment Revenues	0		0		0		0
Depreciation, Depletion and Amortization	19		14		37		28
Basis of Real Estate Sold	0		0		0		0
Other Operating Gain (Loss)	0		0		0		0
Operating Income (Loss)	33		23		64		47
PLUM CREEK TIMBERLANDS L P [Member] | Real Estate [Member]
Segment Reporting Information [Line Items]
External Revenues	77		53		100		131
Intersegment Revenues	0		0		0		0
Depreciation, Depletion and Amortization	0		0		0		0
Basis of Real Estate Sold	25		17		31		42
Other Operating Gain (Loss)	0		0		0		0
Operating Income (Loss)	45		30		57		75
PLUM CREEK TIMBERLANDS L P [Member] | Manufacturing [Member]
Segment Reporting Information [Line Items]
External Revenues	94	[4]	99	[4]	184	[4]	185	[4]
Intersegment Revenues	0	[4]	0	[4]	0	[4]	0	[4]
Depreciation, Depletion and Amortization	6	[4]	4	[4]	9	[4]	8	[4]
Basis of Real Estate Sold	0	[4]	0	[4]	0	[4]	0	[4]
Other Operating Gain (Loss)	2	[4]	0	[4]	2	[4]	0	[4]
Operating Income (Loss)	10	[4]	14	[4]	19	[4]	24	[4]
PLUM CREEK TIMBERLANDS L P [Member] | Energy and Natural Resources [Member]
Segment Reporting Information [Line Items]
External Revenues	9		5		18		11
Intersegment Revenues	0		0		0		0
Depreciation, Depletion and Amortization	2		1		4		1
Basis of Real Estate Sold	0		0		0		0
Other Operating Gain (Loss)	0		0		0		0
Operating Income (Loss)	6		4		12		9
PLUM CREEK TIMBERLANDS L P [Member] | Other Segment [Member]
Segment Reporting Information [Line Items]
External Revenues	5	[2]	0	[2]	8	[2]	0	[2]
Intersegment Revenues	0	[2]	0	[2]	0	[2]	0	[2]
Depreciation, Depletion and Amortization	0	[2]	0	[2]	0	[2]	0	[2]
Basis of Real Estate Sold	0	[2]	0	[2]	0	[2]	0	[2]
Other Operating Gain (Loss)	0	[2]	0	[2]	0	[2]	0	[2]
Operating Income (Loss)	(3)	[2]	0	[2]	(4)	[2]	0	[2]
PLUM CREEK TIMBERLANDS L P [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
External Revenues	356	[3]	303	[3]	673	[3]	643	[3]
Intersegment Revenues	6	[3]	5	[3]	14	[3]	13	[3]
Depreciation, Depletion and Amortization	33	[3]	24	[3]	64	[3]	49	[3]
Basis of Real Estate Sold	25	[3]	17	[3]	31	[3]	42	[3]
Other Operating Gain (Loss)	2	[3]	0	[3]	2	[3]	0	[3]
Operating Income (Loss)	96	[3]	79	[3]	169	[3]	174	[3]
MWV-CLP [Member] | PLUM CREEK TIMBER CO INC [Member]
Segment Reporting Information [Line Items]
Earnings from Unconsolidated Entities	(2)		0		(3)		0
MWV-CLP [Member] | PLUM CREEK TIMBER CO INC [Member] | Northern Resources [Member]
Segment Reporting Information [Line Items]
Earnings from Unconsolidated Entities	0		0		0		0
MWV-CLP [Member] | PLUM CREEK TIMBER CO INC [Member] | Southern Resources [Member]
Segment Reporting Information [Line Items]
Earnings from Unconsolidated Entities	0		0		0		0
MWV-CLP [Member] | PLUM CREEK TIMBER CO INC [Member] | Real Estate [Member]
Segment Reporting Information [Line Items]
Earnings from Unconsolidated Entities	0		0		0		0
MWV-CLP [Member] | PLUM CREEK TIMBER CO INC [Member] | Manufacturing [Member]
Segment Reporting Information [Line Items]
Earnings from Unconsolidated Entities	0	[1]	0	[1]	0	[1]	0	[1]
MWV-CLP [Member] | PLUM CREEK TIMBER CO INC [Member] | Energy and Natural Resources [Member]
Segment Reporting Information [Line Items]
Earnings from Unconsolidated Entities	0		0		0		0
MWV-CLP [Member] | PLUM CREEK TIMBER CO INC [Member] | Other Segment [Member]
Segment Reporting Information [Line Items]
Earnings from Unconsolidated Entities	(2)	[2],[5]	0	[2],[5]	(3)	[2],[5]	0	[2],[5]
MWV-CLP [Member] | PLUM CREEK TIMBER CO INC [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Earnings from Unconsolidated Entities	(2)	[3]	0	[3]	(3)	[3]	0	[3]
MWV-CLP [Member] | PLUM CREEK TIMBERLANDS L P [Member]
Segment Reporting Information [Line Items]
Earnings from Unconsolidated Entities	(2)		0		(3)		0
MWV-CLP [Member] | PLUM CREEK TIMBERLANDS L P [Member] | Northern Resources [Member]
Segment Reporting Information [Line Items]
Earnings from Unconsolidated Entities	0		0		0		0
MWV-CLP [Member] | PLUM CREEK TIMBERLANDS L P [Member] | Southern Resources [Member]
Segment Reporting Information [Line Items]
Earnings from Unconsolidated Entities	0		0		0		0
MWV-CLP [Member] | PLUM CREEK TIMBERLANDS L P [Member] | Real Estate [Member]
Segment Reporting Information [Line Items]
Earnings from Unconsolidated Entities	0		0		0		0
MWV-CLP [Member] | PLUM CREEK TIMBERLANDS L P [Member] | Manufacturing [Member]
Segment Reporting Information [Line Items]
Earnings from Unconsolidated Entities	0	[4]	0	[4]	0	[4]	0	[4]
MWV-CLP [Member] | PLUM CREEK TIMBERLANDS L P [Member] | Energy and Natural Resources [Member]
Segment Reporting Information [Line Items]
Earnings from Unconsolidated Entities	0		0		0		0
MWV-CLP [Member] | PLUM CREEK TIMBERLANDS L P [Member] | Other Segment [Member]
Segment Reporting Information [Line Items]
Earnings from Unconsolidated Entities	(2)	[2],[5]	0	[2],[5]	(3)	[2],[5]	0	[2],[5]
MWV-CLP [Member] | PLUM CREEK TIMBERLANDS L P [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Earnings from Unconsolidated Entities	$ (2)	[3]	$ 0	[3]	$ (3)	[3]	$ 0	[3]

[1] During the second quarter of 2014, the company experienced a fire at its MDF facility. The company recorded a $2 million loss representing the net book value of the building and equipment damaged or destroyed by the fire. During the second quarter of 2014, the company also recorded a $4 million gain related to partial insurance recoveries the company expects to receive. The amount of insurance recoveries was based on the costs incurred during the second quarter to rebuild or replace the damaged building and equipment. Substantially all of these costs were capitalized during the second quarter of 2014. Both the building and equipment loss and the insurance recoveries are reported as Other Operating Gain in the Manufacturing Segment and are included in Other Operating Income (Expense), net in the Consolidated Statements of Income.

[2] The Other Segment includes revenue and expenses associated with our new business of providing timber and wood-fiber procurement services, along with equity earnings (losses) associated with our investments in real estate development ventures. There were no similar activities in 2013.

[3] Consolidated depreciation, depletion and amortization includes unallocated corporate expense of $1 million for each of the quarterly periods ended June 30, 2014 and June 30, 2013, respectively, and includes $2 million for each of the six-month periods ended June 30, 2014 and June 30, 2013, respectively.

[4] During the second quarter of 2014, the Operating Partnership experienced a fire at its MDF facility. The Operating Partnership recorded a $2 million loss representing the net book value of the building and equipment damaged or destroyed by the fire. During the second quarter of 2014, the Operating Partnership also recorded a $4 million gain related to partial insurance recoveries the Operating Partnership expects to receive. The amount of insurance recoveries was based on the costs incurred during the second quarter to rebuild or replace the damaged building and equipment. Substantially all of these costs were capitalized during the second quarter of 2014. Both the building and equipment loss and the insurance recoveries are reported as Other Operating Gain in the Manufacturing Segment and are included in Other Operating Income (Expense), net in the Consolidated Statements of Income.

[5] For Segment reporting, Equity Loss from Real Estate Development Ventures of $2 million and $0 for the quarterly periods ended June 30, 2014 and June 30, 2013, respectively, and Equity Loss from Real Estate Development Ventures of $3 million and $0 for the six-month periods ended June 30, 2014 and June 30, 2013, respectively, are included in Operating Income (Loss) for the Other Segment.