Per Share Data (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions		3 Months Ended		6 Months Ended
	Jul. 10, 2018	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest		$ (279,000)	$ 207,000	$ (393,000)	$ 380,000
Net Income (Loss) Attributable to Noncontrolling Interest		(5,000)	11,000	(8,000)	8,000
Net Income (Loss) Attributable to Parent		$ (274,000)	$ 196,000	$ (385,000)	$ 372,000
Basic weighted average common shares outstanding		4,098	4,061	4,092	4,036
Diluted weighted average common shares outstanding		4,098	4,124	4,092	4,095
Basic net (loss) income per common share		$ (0.07)	$ 0.05	$ (0.09)	$ 0.09
Diluted net (loss) income per common share		$ (0.07)	$ 0.05	$ (0.09)	$ 0.09
Options and RSUs [Member]
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount			6
Options and Restricted Stock Units [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		0	60	0	55
Warrant [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		0	3	0	4
Class of Warrant or Right, Number of Securities Called by Warrants or Rights	55
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 5.25
Proceeds from Warrant Exercises	$ 287,000
Warrant [Member] | SoftBank [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					1
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		73		73	6