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Acquisitions and Divestitures Schedule Of Purchase Price Of Valves & Controls Allocated To Assets And Liabilities (Details) - USD ($) $ in Millions	Jun. 30, 2017	Apr. 28, 2017	Sep. 30, 2016
Business Acquisition [Line Items]
Goodwill	$ 5,296		$ 3,909
Pentair's Valves & Controls [Member]
Business Acquisition [Line Items]
Accounts receivable		$ 363
Inventory		562
Other current assets		27
Property, plant & equipment		405
Goodwill		1,373
Intangibles		988
Other assets		287
Assets held-for-sale, including deferred taxes		38
Total assets		4,043
Accounts payable		119
Other current liabilities		308
Deferred taxes and other liabilities		656
Cash paid, net of cash acquired		$ 2,960