Long-Lived Asset Impairment Charges (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Restructuring Cost and Reserve [Line Items]
Long-lived asset impairment charges	$ 90	$ 30	$ 90	$ 0	$ 8
Other long lived asset impairment
Restructuring Cost and Reserve [Line Items]
Long-lived asset impairment charges				0	1
Self-unloading ocean vessels
Restructuring Cost and Reserve [Line Items]
Long-lived asset impairment charges	60		60
Machinery and equipment | Empire, Nevada and New Orleans, Louisiana
Restructuring Cost and Reserve [Line Items]
Long-lived asset impairment charges			16
Machinery and equipment | Gypsum, Ohio
Restructuring Cost and Reserve [Line Items]
Long-lived asset impairment charges			2
Future manufacturing facilities
Restructuring Cost and Reserve [Line Items]
Long-lived asset impairment charges			12
Closed Gypsum Quarry and Ship Loading Facility
Restructuring Cost and Reserve [Line Items]
Long-lived asset impairment charges			$ 0	$ 0	$ 7