Segments (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	[1]
Net Sales:
Net sales	$ 970	$ 948	$ 1,879	$ 1,798
Operating Profit (Loss):
Operating profit	105	98	181	164
Operating segments | Gypsum
Net Sales:
Net sales	617	612	1,194	1,157
Operating Profit (Loss):
Operating profit	98	95	166	160
Operating segments | Ceilings
Net Sales:
Net sales	131	130	254	255	[2]
Operating Profit (Loss):
Operating profit	25	24	46	39	[2]
Operating segments | Distribution
Net Sales:
Net sales	364	344	698	644
Operating Profit (Loss):
Operating profit	9	4	13	5
Corporate
Operating Profit (Loss):
Operating profit	(24)	(21)	(47)	(42)
Eliminations
Net Sales:
Net sales	(142)	(138)	(267)	(258)
Operating Profit (Loss):
Operating profit	$ (3)	$ (4)	$ 3	$ 2

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