CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME - USD ($) $ in Thousands, shares in Millions	3 Months Ended		6 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Revenue, Net [Abstract]
Service revenue	$ 8,433,000		$ 16,558,000
Revenue, equipment sales, net	1,418,000	$ 994,000	2,591,000	$ 2,181,000
Revenue, equipment rentals, net	1,253,000	966,000	2,465,000	1,865,000
Net operating revenues	8,433,000	7,927,000	16,558,000	16,084,000
Net operating expenses
Cost of Services (exclusive of depreciation and amortization included below)	1,694,000	1,698,000	3,371,000	3,407,000
Cost of equipment sales	1,517,000	1,404,000	2,787,000	2,949,000
Cost of equipment rentals	151,000	112,000	275,000	224,000
Selling, general and administrative	1,861,000	2,013,000	3,728,000	3,951,000
Severance and exit costs	25,000	0	33,000	0
Depreciation, network and other	1,021,000	997,000	2,044,000	1,974,000
Depreciation, equipment rentals	1,181,000	888,000	2,317,000	1,742,000
Amortization	159,000	209,000	330,000	432,000
Other, net	46,000	5,000	80,000	(359,000)
Total costs and expenses	7,655,000	7,326,000	14,965,000	14,320,000
Operating Income	778,000	601,000	1,593,000	1,764,000
Other (expense) income
Interest Expense	(633,000)	(595,000)	(1,270,000)	(1,208,000)
Other income, net	79,000	44,000	121,000	(8,000)
Nonoperating Expense	(554,000)	(551,000)	(1,149,000)	(1,216,000)
Loss (income) before income taxes	224,000	50,000	444,000	548,000
Income tax benefit	(17,000)	(98,000)	(64,000)	(390,000)
Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	207,000	(48,000)	380,000	158,000
Net Income (Loss) Attributable to Noncontrolling Interest	(11,000)	0	(8,000)	0
Net Income (Loss) Attributable to Parent	$ 196,000	$ (48,000)	$ 372,000	$ 158,000
Basic net (loss) income per common share	$ 0.05	$ (0.01)	$ 0.09	$ 0.04
Diluted net (loss) income per common share	$ 0.05	$ (0.01)	$ 0.09	$ 0.04
Basic weighted average common shares outstanding	4,061	3,998	4,036	3,996
Diluted weighted average common shares outstanding	4,124	3,998	4,095	4,080
Other comprehensive (loss) income, net of tax:
Net unrealized holding gains on securities and other	$ 1,000	$ 13,000	$ (7,000)	$ 18,000
Net unrealized holding gains (losses) on derivatives	7,000	2,000	17,000	(7,000)
Net unrecognized net periodic pension and other postretirement benefits	1,000	1,000	3,000	1,000
Cumulative Effect of New Accounting Pronouncement	0		(8,000)
Other comprehensive income	9,000	16,000	5,000	12,000
Comprehensive (loss) income	216,000	(32,000)	385,000	170,000
Services [Member]
Revenue, Net [Abstract]
Service revenue	$ 5,762,000	$ 5,967,000	$ 11,502,000	$ 12,038,000