Composition of Certain Balance Sheet Captions - Composition of Certain Balance Sheet Captions (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Apr. 01, 2019	Mar. 31, 2019
Accounts receivable, net:
Accounts receivable, Billed	$ 208,376		$ 218,276
Accounts receivable, Unbilled	97,460		83,743
Allowance for doubtful accounts	(2,217)		(1,712)
Accounts receivable, net	303,619		300,307
Inventories:
Raw materials	86,130		77,834
Work in process	51,100		52,084
Finished goods	126,603		104,600
Inventories	263,833		234,518
Prepaid expenses and other current assets:
Prepaid expenses	88,326		72,369
Other	18,521		18,277
Prepaid expenses and other current assets	106,847	$ 90,179	90,646
Other acquired intangible assets, net:
Other acquired intangible assets, gross	217,794		217,784
Less: accumulated amortization	(197,440)		(195,483)
Other acquired intangible assets, net	20,354		22,301
Other assets:
Investment in unconsolidated affiliate	158,868		160,711
Deferred income taxes	267,345		258,834
Capitalized software costs, net	242,135		244,368
Patents, orbital slots and other licenses, net	34,536		23,059
Other	76,979		71,833
Other assets	779,863		758,805
Accrued and other liabilities:
Collections in excess of revenues and deferred revenues	123,304		125,540
Accrued employee compensation	30,840		56,454
Accrued vacation	46,107		43,077
Warranty reserve, current portion	6,243		5,877
Operating lease liabilities	40,804
Other	77,587		77,320
Accrued and other liabilities	324,885	346,674	308,268
Other liabilities:
Deferred revenues, long-term portion	85,894		71,230
Deferred rent, long-term portion			16,810
Warranty reserve, long-term portion	2,207		1,707
Satellite performance incentive obligations, long-term portion	25,119		25,324
Other	4,870		5,755
Other liabilities	118,090	$ 104,115	120,826
Technology [Member]
Other acquired intangible assets, net:
Other acquired intangible assets, gross	89,954		89,972
Contracts and Customer Relationships [Member]
Other acquired intangible assets, net:
Other acquired intangible assets, gross	103,294		103,283
Satellite Co-Location Rights [Member]
Other acquired intangible assets, net:
Other acquired intangible assets, gross	8,600		8,600
Trade Name [Member]
Other acquired intangible assets, net:
Other acquired intangible assets, gross	5,940		5,940
Other [Member]
Other acquired intangible assets, net:
Other acquired intangible assets, gross	10,006		9,989
Satellites, Net [Member]
Property and equipment, net:
Property and equipment	1,745,764		1,667,208
Less: accumulated depreciation and amortization	(471,092)		(451,545)
Property and equipment, net	1,274,672		1,215,663
Property and Equipment, Net [Member]
Property and equipment, net:
Property and equipment	1,822,047		1,752,248
Less: accumulated depreciation and amortization	(880,674)		(842,621)
Property and equipment, net	941,373		909,627
Satellites [Member] | Satellites, Net [Member]
Property and equipment, net:
Property and equipment	978,113		978,118
Capital Lease of Satellite Capacity - Anik F2 [Member] | Satellites, Net [Member]
Property and equipment, net:
Property and equipment	99,090		99,090
Construction in Progress [Member] | Satellites, Net [Member]
Property and equipment, net:
Property and equipment	668,561		590,000
Construction in Progress [Member] | Property and Equipment, Net [Member]
Property and equipment, net:
Property and equipment	181,941		167,178
Equipment and Software [Member] | Property and Equipment, Net [Member]
Property and equipment, net:
Property and equipment	1,073,222		1,027,293
CPE Leased Equipment [Member] | Property and Equipment, Net [Member]
Property and equipment, net:
Property and equipment	377,158		373,357
Less: accumulated depreciation and amortization	(148,800)		(142,600)
Furniture and Fixtures [Member] | Property and Equipment, Net [Member]
Property and equipment, net:
Property and equipment	51,042		46,678
Leasehold Improvements [Member] | Property and Equipment, Net [Member]
Property and equipment, net:
Property and equipment	127,470		126,528
Building [Member] | Property and Equipment, Net [Member]
Property and equipment, net:
Property and equipment	8,923		8,923
Land [Member] | Property and Equipment, Net [Member]
Property and equipment, net:
Property and equipment	$ 2,291		$ 2,291