Per Share Data (Narrative) (Details) - $ / shares shares in Millions	3 Months Ended	6 Months Ended
	Sep. 30, 2017	Sep. 30, 2017	Sep. 30, 2016	Mar. 31, 2017
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 5.25	$ 5.25
Document Period End Date		Sep. 30, 2017
Class of Warrant or Right, Unissued	24	24		62
Class of Warrant or Right, Number of Securities Called by Warrants or Rights	20	20		55
Options and RSUs [Member]
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Number of shares that had no effect on computation of dilutive weighted average number of shares outstanding	60	60
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	113		124
Employee Stock Option [Member]
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount		4