Asset Impairment, Exit and Implementation Costs (Facilities Consolidation) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2017	Dec. 31, 2016
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 27	$ 122
Asset impairment and exit costs	4	120
Other restructuring costs	23	$ 2
Payments for restructuring	20
Facilities Consolidation [Member]
Restructuring Cost and Reserve [Line Items]
Expected restructuring charges	$ 150		$ 150
Expected restructuring charges, per share (usd per share)	$ 0.05		$ 0.05
Restructuring charges	$ 27		$ 98	$ 71
Charges (in usd per share)				$ 0.03
Restructuring and related cost, expected cost fiscal year	70		70
Charges expected to result in cash expenditures	90
Payments for restructuring	11		16
Facilities Consolidation [Member] | Accelerated Depreciation [Member]
Restructuring Cost and Reserve [Line Items]
Expected restructuring charges	55		55
Facilities Consolidation [Member] | Employee Separation Costs [Member]
Restructuring Cost and Reserve [Line Items]
Expected restructuring charges	45		45
Facilities Consolidation [Member] | Other Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Expected restructuring charges	$ 50		$ 50