Divestiture of a Business (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended
	Aug. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Noncash or Part Noncash Divestitures [Line Items]
Gain from sale of business, pre-tax				$ (113)	$ 102
Operating Segments | ZEE Medical Business | Total Distribution Solutions
Noncash or Part Noncash Divestitures [Line Items]
Proceeds from divestiture of businesses	$ 134
Gain from sale of business, pre-tax		$ 52			52
Gain from sale of business, after tax		$ 33			29
Operating Segments | Nurse Triage | Technology Solutions
Noncash or Part Noncash Divestitures [Line Items]
Proceeds from divestiture of businesses			$ 84
Gain from sale of business, pre-tax			51		$ 51
Gain from sale of business, after tax			$ 38