The Company and a Summary of Its Significant Accounting Policies - Additional Information (Detail 6) - USD ($) $ in Millions	12 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Mar. 31, 2023
Company And Summary Of Significant Accounting Policies [Line Items]
Increase (decrease) in collections in excess of revenues and deferred revenues	$ 33.8
Increase (decrease) in unbilled accounts receivable	24.5
Collections in excess of revenues and deferred revenues, recognized revenue	$ 238.6	$ 97.8
Funded Research and Development from Customer Contracts [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Percentage of revenue	11.00%	12.00%	16.00%
Fixed-price Contract [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Percentage of revenue	96.00%	95.00%	93.00%
U.S. Government as an Individual Customer [Member]
Company And Summary Of Significant Accounting Policies [Line Items]
Percentage of revenue	18.00%	17.00%	17.00%

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-8

+ Details

Name:	us-gaap_ContractWithCustomerLiabilityRevenueRecognized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of increase (decrease) in right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

+ Details

Name:	us-gaap_IncreaseDecreaseInContractWithCustomerAsset
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of increase (decrease) in obligation to transfer good or service to customer for which consideration has been received or is receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 912
-SubTopic 310
-Name Accounting Standards Codification
-Section 45
-Paragraph 11
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478345/912-310-45-11

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

+ Details

Name:	us-gaap_IncreaseDecreaseInContractWithCustomerLiability
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Extended line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	vsat_CompanyAndSummaryOfSignificantAccountingPoliciesLineItems
Namespace Prefix:	vsat_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

No definition available.

+ Details

Name:	vsat_RevenueFromContractWithCustomerExcludingAssessedTaxPercentage
Namespace Prefix:	vsat_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	srt_ProductOrServiceAxis=vsat_FundedResearchAndDevelopmentContractsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ContractWithCustomerBasisOfPricingAxis=us-gaap_FixedPriceContractMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_MajorCustomersAxis=vsat_USGovernmentAsAnIndividualCustomerMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: