Segments (Details 1) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Restructuring and long-lived asset impairment charges by segment
Restructuring, Settlement and Impairment Provisions	$ 3	$ 59	$ 5	$ 70
North American Gypsum [Member]
Restructuring and long-lived asset impairment charges by segment
Restructuring, Settlement and Impairment Provisions	1	52	4	61
Worldwide Ceilings [Member]
Restructuring and long-lived asset impairment charges by segment
Restructuring, Settlement and Impairment Provisions	0	0	1	0
Building Products Distribution [Member]
Restructuring and long-lived asset impairment charges by segment
Restructuring, Settlement and Impairment Provisions	2	7	0	8
Corporate [Member]
Restructuring and long-lived asset impairment charges by segment
Restructuring, Settlement and Impairment Provisions	$ 0	$ 0	$ 0	$ 1