Segments (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014		Sep. 30, 2015	Sep. 30, 2014
Net Sales:
Net sales	$ 972	$ 972		$ 2,851	$ 2,770	[1]
Operating Profit (Loss):
Operating profit	102	22		283	186	[1]
Long-lived asset impairment charges	0	30		0	30
Litigation settlement charge	0	(48)		0	(48)
Gypsum
Operating Profit (Loss):
Long-lived asset impairment charges					30
Operating segments | Gypsum
Net Sales:
Net sales	610	621		1,804	1,778	[1]
Operating Profit (Loss):
Operating profit	89	12	[2]	255	172	[1],[2]
Operating segments | Ceilings
Net Sales:
Net sales	130	137		384	392	[1],[3]
Operating Profit (Loss):
Operating profit	24	30		70	69	[1],[3]
Operating segments | Distribution
Net Sales:
Net sales	378	359		1,076	1,003	[1]
Operating Profit (Loss):
Operating profit	9	4		22	9	[1]
Corporate
Operating Profit (Loss):
Operating profit	(25)	(23)		(72)	(65)	[1]
Eliminations
Net Sales:
Net sales	(146)	(145)		(413)	(403)	[1]
Operating Profit (Loss):
Operating profit	$ 5	$ (1)		$ 8	$ 1	[1]

[1] Net sales and operating profit (loss) have been recast for the periods prior to April 1, 2014 to conform with the new presentation of reportable segments.

[2] Gypsum's operating profit for both the three and nine months ended September 30, 2014 included long-lived asset impairment charges of $30 million and a litigation settlement charge of $48 million. See notes 3 and 17, respectively.

[3] Ceilings' net sales and operating profit for the nine months ended September 30, 2014 includes the results, through February 27, 2014, of our wholly-owned subsidiaries and consolidated joint ventures that were contributed to UBBP.