The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

+ Details

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(12))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(10))
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66022249&loc=d3e33749-111570

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(13)(f))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

+ Details

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

- Definition

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:	us-gaap_ScheduleOfEquityMethodInvestmentsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The maximum useful life of the basis difference assigned to finite-lived intangible assets in 'PnYnMdDTnHnMnS' format (the basis difference defined as the difference between the amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee).

+ References

No definition available.

+ Details

Name:	vsat_IntangibleAssetsBasisDifferenceMaximumUsefulLife
Namespace Prefix:	vsat_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The weighted average amortization period of the basis difference assigned to finite-lived intangible assets, in 'PnYnMdDTnHnMnS' format (the basis difference defined as the difference between the amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee).

+ References

No definition available.

+ Details

Name:	vsat_IntangibleAssetsBasisDifferenceWeightedAverageUsefulLife
Namespace Prefix:	vsat_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The net of transaction cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

+ References

No definition available.

+ Details

Name:	vsat_PaymentsToAcquireEquityMethodInvestmentsNetOfTransactionCosts
Namespace Prefix:	vsat_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The maximum useful life of the portion of the basis difference assigned to tangible assets, in 'PnYnMdDTnHnMnS' format (the basis difference defined as the difference between the amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee).

+ References

No definition available.

+ Details

Name:	vsat_TangibleAssetsBasisDifferenceMaximumUsefulLife
Namespace Prefix:	vsat_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The weighted average amortization period of the basis difference assigned to tangible assets, in 'PnYnMdDTnHnMnS' format (the basis difference defined as the difference between the amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee).

+ References

No definition available.

+ Details

Name:	vsat_TangibleAssetsBasisDifferenceWeightedAverageUsefulLife
Namespace Prefix:	vsat_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=vsat_EuroInfrastructureCoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Equity Method Investments and Related-Party Transactions - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2017	Mar. 31, 2017	Jun. 30, 2016
Schedule of Equity Method Investments [Line Items]
Income (loss) from equity method investments	$ (513)
Euro Infrastructure Co [Member]
Schedule of Equity Method Investments [Line Items]
Payments, net of transaction costs, to acquire the issued shares in investment		$ 139,500
Equity method investment ownership percentage		49.00%
Estimated useful life, years	11 years
Estimated weighted average life (In years)	10 years
Tangible assets, useful life	11 years
Tangible assets, weighted average useful life	11 years
Income (loss) from equity method investments	$ (500)		$ 0