Divestiture of Business (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Jun. 30, 2015	Dec. 31, 2016	Dec. 31, 2015
Noncash or Part Noncash Divestitures [Line Items]
Gain from sale of business, pre-tax			$ (113)	$ 103
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
Gain from sale of business, after tax				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