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Revenue Derived From Services, Percentage

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The net result for the period of deducting operating expenses from operating revenues.

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Cash received for the settlement of litigation during the current period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Segments of Business - Narrative (Details) $ in Millions	3 Months Ended				12 Months Ended
Segments of Business - Narrative (Details) $ in Millions	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2016 USD ($) segment	Mar. 31, 2015 USD ($)	Mar. 31, 2014 USD ($)
Segment Reporting [Abstract]
Number of operating segments \| segment					2
Segment Reporting Information [Line Items]
Pretax charges					$ 3,545	$ 2,968	$ 2,439
Pre-tax gain					103	0	0
Pre-tax charge	$ 229				229
Operating Segments
Segment Reporting Information [Line Items]
Pretax charges					4,072	$ 3,485	$ 2,920
Corporate
Segment Reporting Information [Line Items]
Pre-tax charge	17				$ 17
Distribution Solutions \| Operating Segments
Segment Reporting Information [Line Items]
Percentage of total revenue (less than) (as a percent)					2.00%	2.00%	2.00%
Pretax charges					$ 3,553	$ 3,047	$ 2,472
Net cash proceeds		$ 17		$ 59	76
Pre-tax charge	161				161
Distribution Solutions \| Operating Segments \| ZEE Medical Business
Segment Reporting Information [Line Items]
Pre-tax gain			$ 52		52
Distribution Solutions \| Operating Segments \| LIFO method of accounting
Segment Reporting Information [Line Items]
Pretax charges					244	337	311
Technology Solutions \| Operating Segments
Segment Reporting Information [Line Items]
Pretax charges					519	438	$ 448
Pre-tax charge	$ 51				51
Technology Solutions \| Operating Segments \| Nurse Triage
Segment Reporting Information [Line Items]
Pre-tax gain				$ 51	$ 51
Technology Solutions \| Operating Segments \| International Technology, Workforce
Segment Reporting Information [Line Items]
Non-cash pre-tax charge						$ 34