The Company and a Summary of Its Significant Accounting Policies - Additional Information (Detail 2) - USD ($)	1 Months Ended	3 Months Ended	12 Months Ended
	Apr. 30, 2025	Mar. 31, 2025	Mar. 31, 2025	Mar. 31, 2024	Mar. 31, 2023
Company And Summary Of Significant Accounting Policies [Line Items]
Capitalized interest expense			$ 215,400,000	$ 227,500,000	$ 159,700,000
Insurance claim receivables		$ 10,000,000	10,000,000	261,500,000
Insurance recovery proceeds			251,500,000	508,560,000
Capitalized costs, net, related to software developed for resale		780,300,000	780,300,000	723,900,000
Gross capitalized implementation costs incurred in cloud computing arrangements		88,700,000	88,700,000	63,600,000
Accumulated amortization related to capitalized software developed for resale		515,800,000	515,800,000	483,300,000
Accumulated amortization related to capitalized implementation costs incurred in cloud computing arrangements		18,400,000	18,400,000	9,500,000
Total capitalized costs related to patents, orbital slots and other licenses		129,400,000	129,400,000	120,900,000
Accumulated amortization of patents, orbital slots and other licenses		10,200,000	10,200,000	8,400,000
Patents, orbital slots and other licenses amortization expense			1,900,000
Debt issuance costs capitalized			35,600,000	53,900,000	0
Capitalized cost related to software development for resale			78,400,000	77,500,000
Amortization expense of capitalized software development costs			54,500,000	59,100,000	54,400,000
Amortization of capitalized implementation costs incurred in cloud computing arrangements			8,800,000	4,200,000
Goodwill and other intangible assets impairment			0	0	$ 0
Self-insurance liability		$ 5,900,000	$ 5,900,000	$ 6,500,000
Revenue, practical expedient, financing component			true	true	true
Revenue, practical expedient, incremental cost of obtaining contract [true false]			true	true	true
Asset Impairment			$ 0	$ 0	$ 0
Minimum [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Property, equipment and satellites, estimated useful life (years)		2 years	2 years
Expected capitalized software developed for resale over each of the next five fiscal years, estimated based on annual minimum straight-line amortization		$ 30,000,000	$ 30,000,000
Estimated useful life, years		2 years	2 years
Maximum [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Property, equipment and satellites, estimated useful life (years)		38 years	38 years
Expected capitalized software developed for resale over each of the next five fiscal years, estimated based on annual minimum straight-line amortization		$ 60,000,000	$ 60,000,000
Estimated useful life, years		12 years	12 years
Maximum [Member] | Software Development Costs [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Estimated useful life, years		5 years	5 years
Internally Developed Software [Member] | Minimum [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Property, equipment and satellites, estimated useful life (years)		3 years	3 years
Internally Developed Software [Member] | Maximum [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Property, equipment and satellites, estimated useful life (years)		7 years	7 years
CPE Leased Equipment [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Property, equipment and satellites		$ 525,972,000	$ 525,972,000	567,548,000
Accumulated depreciation and amortization		$ 328,000,000	$ 328,000,000	267,400,000
CPE Leased Equipment [Member] | Minimum [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Property, equipment and satellites, estimated useful life (years)		4 years	4 years
CPE Leased Equipment [Member] | Maximum [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Property, equipment and satellites, estimated useful life (years)		7 years	7 years
ViaSat-3 F1 satellite [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Maximum expected recovery % of the planned throughput			10.00%
Satellites [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Reduction to carrying value including capitalized interest				1,670,000,000
Insurance claim receivables				770,000,000
Insurance recovery proceeds			$ 251,500,000	508,600,000
Impairment charges and other liabilities		$ 169,400,000
Satellites [Member] | Subsequent Event [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Insurance recovery proceeds	$ 10,000,000
Satellites [Member] | Selling General and Administrative Expenses [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Satellite impairment loss, net, including liabilities associated with the termination of certain subcontractor agreements				$ 905,500,000
Satellites [Member] | Minimum [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Property, equipment and satellites, estimated useful life (years)		7 years	7 years
Satellites [Member] | Maximum [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Property, equipment and satellites, estimated useful life (years)		17 years	17 years