Stockholders' Equity Stockholders' Equity (Other Comprehensive Income (Loss), Net of Tax) (Parentheticals) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Stockholders' Equity Attributable to Parent [Abstract]
Foreign currency translation adjustments arising during period, income tax expense of $2 and $4	$ 2	$ 4
Unrealized losses on cash flow hedges arising during period, income tax expense of nil and nil	0	0
Amortization of actuarial loss, prior service cost and transition obligation, income tax (benefit) of ($4) and ($3)	(4)	(3)
Foreign currency translation adjustments, income tax expense of nil and nil	$ 0	$ 0