Industry Segment and Geographic Data (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Financial information for each reportable segment
Revenue	$ 969	$ 931	$ 966	$ 925	$ 1,003	$ 939	$ 971	$ 890	$ 3,791	$ 3,803	$ 3,202
Operating income	104	111	129	99	100	79	116	100	443	395	388
Other non-operating income, net									0	5	0
Interest Expense									55	17	0
Income before taxes									388	383	388
Depreciation and amortization									142	137	92
Capital expenditures									112	126	94
Water Infrastructure
Financial information for each reportable segment
Revenue									2,425	2,416	1,930
Operating income									342	343	276
Depreciation and amortization									106	104	60
Capital expenditures									79	91	55
Applied Water
Financial information for each reportable segment
Revenue									1,424	1,444	1,327
Operating income									170	160	158
Depreciation and amortization									29	31	30
Capital expenditures									27	31	38
Eliminations
Financial information for each reportable segment
Revenue									(58)	(57)	(55)
Corporate and other
Financial information for each reportable segment
Operating income									(69)	(108)	(46)
Depreciation and amortization									7	2	2
Capital expenditures									$ 6	$ 4	$ 1