Segment Information (Details 1) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Total assets for each reportable segment
Total assets	$ 4,596	$ 4,393
Water Infrastructure
Total assets for each reportable segment
Total assets	2,831	2,745
Applied Water
Total assets for each reportable segment
Total assets	1,280	1,234
Corporate and other
Total assets for each reportable segment
Total assets	$ 485	$ 414