Income Taxes Temporary Differences And Carryforwards in Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Income Tax Disclosure [Abstract]
Deferred Tax Expense from Stock Options Exercised	$ 180
Deferred tax assets
Accrued expenses and reserves	1,404	$ 210
Employee and retiree benefits	515	270
Net operating loss and other credit carryforwards	4,668	2,471
Research and development	94	64
Joint ventures and partnerships	279	231
Deferred Tax Assets, Other	35	16
Gross deferred tax assets	6,995	3,262
Valuation allowances	(3,564)	(1,256)
Net deferred tax assets	3,431	2,006
Net deferred tax asset	1,308	1,482
Deferred tax liabilities
Property, plant and equipment	113	124
Intangible assets	2,010	400
Net deferred tax liabilities	$ 2,123	$ 524