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GOODWILL AND OTHER INTANGIBLE ASSETS Textuals (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Apr. 30, 2019	Apr. 30, 2018	Apr. 30, 2019	Apr. 30, 2018
Finite-Lived Intangible Assets
Additions to goodwill			$ 142
Addition to other intangible assets			102
Impairment of IPR&D	$ 0	$ 0	0	$ 0
Goodwill impairment	0	0	0	0
Amortization of intangible assets during the period	26	$ 26	55	$ 52
Life Sciences and Applied Markets
Finite-Lived Intangible Assets
Additions to goodwill			153
Diagnostics and Genomics
Finite-Lived Intangible Assets
Measurement period adjustment to goodwill			$ (11)
ACEA Biosciences, Inc.
Acquisition
Purchase Price	$ 250