Composition of Certain Balance Sheet Captions - Composition of Certain Balance Sheet Captions (Detail) - USD ($)	Mar. 31, 2023	Mar. 31, 2022
Accounts receivable, net:
Accounts receivable, Billed	$ 327,148,000	$ 233,948,000
Accounts receivable, Unbilled	104,889,000	85,383,000
Allowance for doubtful accounts	(12,103,000)	(7,159,000)
Accounts receivable, net	419,934,000	312,172,000
Inventories:
Raw materials	68,655,000	62,520,000
Work in process	25,347,000	21,702,000
Finished goods	174,561,000	113,642,000
Inventories	268,563,000	197,864,000
Prepaid expenses and other current assets:
Prepaid expenses	115,701,000	102,433,000
Other	60,928,000	38,953,000
Prepaid expenses and other current assets	176,629,000	141,386,000
Property, equipment and satellites, net:
Property, equipment and satellites, gross	6,710,243,000	5,719,303,000
Less: accumulated depreciation and amortization	(2,331,960,000)	(2,014,312,000)
Property and equipment, net	4,378,283,000	3,704,991,000
Other assets:
Deferred income taxes	23,724,000	304,642,000
Capitalized software costs, net	222,155,000	217,159,000
Patents, orbital slots and other licenses, net	73,932,000	62,200,000
Other	146,227,000	115,279,000
Other assets	466,038,000	699,280,000
Accrued and other liabilities:
Collections in excess of revenues and deferred revenues	132,187,000	131,623,000
Accrued employee compensation	125,349,000	108,456,000
Accrued vacation	45,177,000	48,097,000
Warranty reserve, current portion	2,806,000	2,804,000
Operating lease liabilities	$ 50,639,000	$ 49,988,000
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Accrued and other liabilities	Accrued and other liabilities
Income taxes payable	$ 113,905,000	$ 7,872,000
Other	177,169,000	133,724,000
Accrued and other liabilities	647,232,000	482,564,000
Other liabilities:
Deferred revenues, long-term portion	84,747,000	88,983,000
Warranty reserve, long-term portion	2,544,000	2,548,000
Satellite performance incentive obligations, long-term portion	14,654,000	18,651,000
Deferred income taxes	85,989,000	16,869,000
Other	30,608,000	26,105,000
Other liabilities	218,542,000	153,156,000
Equipment and Software [Member]
Property, equipment and satellites, net:
Property, equipment and satellites, gross	1,917,243,000	1,676,736,000
CPE Leased Equipment [Member]
Property, equipment and satellites, net:
Property, equipment and satellites, gross	395,427,000	395,539,000
Less: accumulated depreciation and amortization	(213,600,000)	(210,600)
Furniture and Fixtures [Member]
Property, equipment and satellites, net:
Property, equipment and satellites, gross	58,807,000	57,847,000
Leasehold Improvements [Member]
Property, equipment and satellites, net:
Property, equipment and satellites, gross	151,827,000	149,982,000
Building [Member]
Property, equipment and satellites, net:
Property, equipment and satellites, gross	12,487,000	12,440,000
Land [Member]
Property, equipment and satellites, net:
Property, equipment and satellites, gross	3,873,000	3,944,000
Construction in Progress [Member]
Property, equipment and satellites, net:
Property, equipment and satellites, gross	685,646,000	381,679,000
Satellites [Member]
Property, equipment and satellites, net:
Property, equipment and satellites, gross	1,056,313,000	1,059,182,000
Satellite Ka-band Capacity Obtained under Finance Leases [Member]
Property, equipment and satellites, net:
Property, equipment and satellites, gross	175,712,000	173,480,000
Satellites under Construction [Member]
Property, equipment and satellites, net:
Property, equipment and satellites, gross	$ 2,252,908,000	$ 1,808,474,000