Basis of Presentation - Additional Information (Detail)	3 Months Ended
	Jun. 30, 2024 USD ($) Segment shares	Jun. 30, 2023 USD ($) shares	Sep. 30, 2024 USD ($)	Mar. 31, 2024 USD ($) shares
Company And Summary Of Significant Accounting Policies [Line Items]
Revenue, practical expedient, financing component	true
Remaining performance obligations	$ 3,600,000,000
Number of reportable segments | Segment	2
Increase in collections in excess of revenues and deferred revenues	$ 17,400,000
Collections in excess of revenues and deferred revenues, recognized revenue	106,300,000	$ 53,800,000
Capitalized interest expense	$ 56,600,000	56,700,000
Proportion of insured amount to asset net book value	On July 12, 2023, the Company reported a reflector deployment issue that materially impacted the performance of the ViaSat-3 F1 satellite. The Company and the reflector provider conducted a rigorous review of the development and deployment of the affected reflector to determine its impact and potential remedial measures. In connection with the root cause analysis, the Company determined that while the satellite payload is functional, the Company will recover less than 10% of the planned throughput on the ViaSat-3 F1 satellite.
Operating lease, existence of option to terminate	true
Operating lease, option to terminate, description	some of which include renewal options, and some of which include options to terminate the leases within one year.
Total capitalized costs related to patents	$ 4,000,000			$ 3,900,000
Total capitalized costs related to orbital slots and other licenses	119,800,000			117,000,000
Accumulated amortization of patents, orbital slots and other licenses	8,800,000			8,400,000
Debt issuance costs capitalized	0	41,200,000
Self-insurance liability	6,600,000			6,500,000
Repurchase and immediate retirement of treasury shares pursuant to vesting of certain RSU agreements | value	1,415,000	2,212,000
Stock-based compensation expense	19,182,000	21,752,000
Insurance claim receivables	182,000,000			261,500,000
Continuing Operations [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Stock-based compensation expense	$ 19,200,000	$ 21,800,000
Accounting Standards Update 2022-03 [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Description of new accounting pronouncements	In June 2022, the FASB issued ASU 2022-03, Fair Value Measurement (Topic 820): Fair Value Measurement of Equity Securities Subject to Contractual Sale Restrictions. ASU 2022-03 clarifies that a contractual restriction on the sale of an equity security is not considered in measuring the security's fair value. The standard also requires certain disclosures for equity securities that are subject to contractual restrictions. The Company adopted the new guidance in the first quarter of fiscal year 2025 and the guidance did not have a material impact on its consolidated financial statements and disclosures.
Accounting Standards Update 2023-01 [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Description of new accounting pronouncements	In March 2023, the FASB issued ASU 2023-01, Leases (Topic 842) – Common Control Agreements. The amendments in this update that apply to public business entities clarify the accounting for leasehold improvements associated with common control leases. The Company adopted the new guidance in the first quarter of fiscal year 2025 and the guidance did not have a material impact on its consolidated financial statements and disclosures.
Accounting Standards Update 2023-06 [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Description of new accounting pronouncements	In October 2023, the FASB issued ASU 2023-06, Disclosure Improvements: Codification Amendments in Response to the SEC’s Disclosure Update and Simplification Initiative. This ASU amends certain disclosure and presentation requirements for a variety of topics within the FASB ASC. These amendments will also align the requirements in the ASC with the SEC's regulations. The effective date for each amended topic in the ASC is the date on which the SEC’s removal of the related disclosure requirement from Regulation S-X or Regulation S-K becomes effective, and will not be effective if the SEC has not removed the applicable disclosure requirements by June 30, 2027. Early adoption is prohibited. The Company is currently evaluating the impact of this standard on its consolidated financial statements and disclosures.
Accounting Standards Update 2023-07 [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Description of new accounting pronouncements	In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. This ASU requires public entities to enhance disclosures about their reportable segments' significant expenses on an interim and annual basis. The new standard will become effective for the Company's annual disclosures beginning in fiscal year 2025 and for interim disclosures beginning in fiscal year 2026 on a retrospective basis. Early adoption is permitted. The Company is currently evaluating the impact of this standard on its consolidated financial statements and disclosures.
Accounting Standards Update 2023-09 [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Description of new accounting pronouncements	In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures. ASU 2023-09 enhances income tax disclosures by requiring disclosure of specific categories in the income tax rate reconciliation table and disaggregation of income taxes paid. The new standard will become effective for the Company beginning in fiscal year 2026. Early adoption is permitted and the new standard should be applied prospectively, however retrospective application is permitted. The Company is currently evaluating the impact of this standard on its consolidated financial statement disclosures.
Accounting Standards Update 2024-02 [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Description of new accounting pronouncements	In March 2024, the FASB issued ASU 2024-02, Codification Improvements – Amendments to Remove References to the Concepts Statements. This update contains amendments to the Codification that remove references to various Concepts Statements. The amendments in this update are not intended to result in significant accounting changes for most entities. The amendments in this update are effective for the Company beginning in fiscal year 2026. Early adoption is permitted. The Company is currently evaluating the impact of this standard on its consolidated financial statements and disclosures.
CPE Leased Equipment [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Property, equipment and satellites, cost	$ 554,648,000			567,548,000
Accumulated depreciation and amortization	$ 286,500,000			267,400,000
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
Unfavorable Regulatory Action [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Accrued reserves	$ 7,400,000			16,600,000
Indemnification Guarantee [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Accrued reserves	$ 0			$ 0
Common Stock [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Common stock issued based on the vesting terms of certain restricted stock unit agreements | shares	220,113	137,469
Common Stock Held in Treasury [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Shares of common stock outstanding | shares	0			0
Repurchase and immediate retirement of treasury shares pursuant to vesting of certain RSU agreements, shares | shares	85,638	48,850
Repurchase and immediate retirement of treasury shares pursuant to vesting of certain RSU agreements | value	$ 1,400,000	$ 2,200,000