New Accounting Pronouncements - Cumulative Effects of Accounting Standards Update on Statement of Comprehensive Income and Balance Sheet (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions	3 Months Ended		9 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Service revenue	$ 8,601,000		$ 25,159,000
Revenue, equipment sales, net	1,589,000	$ 1,262,000	4,180,000	$ 3,443,000
Revenue, equipment rentals, net	1,313,000	1,047,000	3,778,000	2,912,000
Revenues	8,601,000	8,239,000	25,159,000	24,323,000
Cost of Services (exclusive of depreciation and amortization included below)	1,648,000	1,733,000	5,019,000	5,140,000
Cost of equipment sales	1,734,000	1,673,000	4,521,000	4,622,000
Cost of equipment rentals	182,000	123,000	457,000	347,000
Selling, general and administrative	2,003,000	2,108,000	5,731,000	6,059,000
Severance and exit costs	(30,000)		(63,000)	(13,000)
Depreciation, network and other	1,088,000	987,000	3,132,000	2,961,000
Depreciation, equipment rentals	1,137,000	990,000	3,454,000	2,732,000
Amortization	145,000	196,000	475,000	628,000
Other, net	185,000	(298,000)	298,000	(657,000)
Total costs and expenses	8,122,000	7,512,000	23,087,000	21,832,000
Operating Income	479,000	727,000	2,072,000	2,491,000
Total other expense	(632,000)	(623,000)	(1,781,000)	(1,839,000)
Loss (income) before income taxes	(153,000)	104,000	291,000	652,000
Income tax benefit	8,000	7,052,000	(56,000)	6,662,000
Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	(145,000)	7,156,000	235,000	7,314,000
Net Income (Loss) Attributable to Noncontrolling Interest	4,000	6,000	(4,000)	6,000
Net Income (Loss) Attributable to Parent	$ (141,000)	$ 7,162,000	$ 231,000	$ 7,320,000
Basic net (loss) income per common share	$ (0.03)	$ 1.79	$ 0.06	$ 1.83
Diluted net (loss) income per common share	$ (0.03)	$ 1.76	$ 0.06	$ 1.79
Basic weighted average common shares outstanding	4,078	4,001	4,050	3,998
Diluted weighted average common shares outstanding	4,078	4,061	4,110	4,080
Change | Accounting Standards Update 2014-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue, equipment sales, net	$ 325,000		$ 957,000
Revenue, equipment rentals, net	(16,000)		(49,000)
Revenues	110,000		393,000
Cost of Services (exclusive of depreciation and amortization included below)	(23,000)		(54,000)
Cost of equipment sales	19,000		90,000
Cost of equipment rentals	0		0
Selling, general and administrative	(142,000)		(316,000)
Depreciation, network and other	0		0
Depreciation, equipment rentals	0		0
Amortization	0		0
Other, net	0		0
Total costs and expenses	(146,000)		(280,000)
Operating Income	256,000		673,000
Total other expense	0		0
Loss (income) before income taxes	256,000		673,000
Income tax benefit	(54,000)		(141,000)
Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	202,000		532,000
Net Income (Loss) Attributable to Noncontrolling Interest	0		0
Net Income (Loss) Attributable to Parent	$ 202,000		$ 532,000
Basic net (loss) income per common share	$ 50,000		$ 130,000
Diluted net (loss) income per common share	$ 50,000		$ 130,000
Basic weighted average common shares outstanding	0		0
Diluted weighted average common shares outstanding	0		60
Balances without adoption of Topic 606
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue, equipment sales, net	$ 1,264,000		$ 3,223,000
Revenue, equipment rentals, net	1,329,000		3,827,000
Revenues	8,491,000		24,766,000
Cost of Services (exclusive of depreciation and amortization included below)	1,671,000		5,073,000
Cost of equipment sales	1,715,000		4,431,000
Cost of equipment rentals	182,000		457,000
Selling, general and administrative	2,145,000		6,047,000
Depreciation, network and other	1,088,000		3,132,000
Depreciation, equipment rentals	1,137,000		3,454,000
Amortization	145,000		475,000
Other, net	185,000		298,000
Total costs and expenses	8,268,000		23,367,000
Operating Income	223,000		1,399,000
Total other expense	(632,000)		(1,781,000)
Loss (income) before income taxes	(409,000)		(382,000)
Income tax benefit	62,000		85,000
Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	(347,000)		(297,000)
Net Income (Loss) Attributable to Noncontrolling Interest	4,000		(4,000)
Net Income (Loss) Attributable to Parent	$ (343,000)		$ (301,000)
Basic net (loss) income per common share	$ (80,000)		$ (70,000)
Diluted net (loss) income per common share	$ (80,000)		$ (70,000)
Basic weighted average common shares outstanding	4,078		4,050
Diluted weighted average common shares outstanding	4,078		4,050
Services [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Service revenue	$ 5,699,000	$ 5,930,000	$ 17,201,000	$ 17,968,000
Services [Member] | Change | Accounting Standards Update 2014-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Service revenue	(199,000)		(515,000)
Services [Member] | Balances without adoption of Topic 606
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Service revenue	$ 5,898,000		$ 17,716,000