Commitments - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Long-term Purchase Commitment [Line Items]
Satellite performance incentives obligation, Noncurrent	$ 24,349	$ 25,324
Satellite Capacity Agreements [Member]
Long-term Purchase Commitment [Line Items]
Future minimum payments on purchase commitments for fiscal year 2021	87,600
Future minimum payments on purchase commitments for fiscal year 2022	47,100
Future minimum payments on purchase commitments for fiscal year 2023	31,000
Future minimum payments on purchase commitments for fiscal year 2024	2,400
ViaSat-1 and ViaSat-2 Satellites [Member]
Long-term Purchase Commitment [Line Items]
Satellite performance incentives obligation	27,400
Satellite performance incentives obligation, current	3,100
Satellite performance incentives obligation, Noncurrent	24,300
ViaSat-1 and ViaSat-2 Satellites [Member] \| Satellite Performance Incentives Obligation [Member]
Long-term Purchase Commitment [Line Items]
Commitment amount	34,300
Future minimum payments under satellite performance incentives obligation for fiscal year 2021	2,800
Future minimum payments under satellite performance incentives obligation for fiscal year 2022	4,500
Future minimum payments under satellite performance incentives obligation for fiscal year 2023	5,000
Future minimum payments under satellite performance incentives obligation for fiscal year 2024	5,300
Future minimum payments under satellite performance incentives obligation for fiscal year 2025	5,200
Future minimum payments under satellite performance incentives obligation thereafter	$ 11,500

The minimum amount the entity agreed to spend under the long-term purchase commitment.

No definition available.

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- 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.

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- Definition

Minimum amount of purchase arrangement maturing after the fifth fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

+ References

No definition available.

+ Details

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- Definition

Minimum amount of purchase arrangement maturing in the fifth fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

+ References

No definition available.

+ Details

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- Definition

Minimum amount of purchase arrangement maturing in the fourth fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

+ References

No definition available.

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- Definition

Minimum amount of purchase arrangement maturing in the next fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

+ References

No definition available.

+ Details

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- Definition

Minimum amount of purchase arrangement maturing in the second fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

+ References

No definition available.

+ Details

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- Definition

Minimum amount of purchase arrangement maturing in the third fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

+ References

No definition available.

+ Details

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77896938&loc=d3e25336-109308

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Aggregate carrying amount of satellite performance incentives obligation as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Satellite performance incentives obligation current.

+ References

No definition available.

+ Details

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- Definition

Carrying amount of satellite performance incentives obligation as of the balance sheet date, of noncurrent obligation. Noncurrent liabilities are expected to be paid after one year (or the normal operating cycle, if longer).

+ References

No definition available.

+ Details

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- Details

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