Property, Plant and Equipment (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Property, Plant and Equipment [Line Items]
Increase (Decrease) in Accounts Payable	$ 1,200	$ 2,000
Leased devices [Member]
Property, Plant and Equipment [Line Items]
Increase (Decrease) in Accounts Payable	207
Increase (Decrease) in Inventories	$ 808