Commitments - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Long-term Purchase Commitment [Line Items]
Satellite performance incentives obligation, Noncurrent	$ 22,191	$ 24,349
Satellite Capacity Agreements [Member]
Long-term Purchase Commitment [Line Items]
Future minimum payments on purchase commitments for fiscal year 2022	57,200
Future minimum payments on purchase commitments for fiscal year 2023	46,600
Future minimum payments on purchase commitments for fiscal year 2024	16,800
Future minimum payments on purchase commitments for fiscal year 2025	5,900
Future minimum payments on purchase commitments for fiscal year 2026	9,700
Future minimum payments on purchase commitments thereafter	65,400
ViaSat-1 and ViaSat-2 Satellites [Member]
Long-term Purchase Commitment [Line Items]
Satellite performance incentives obligation	27,100
Satellite performance incentives obligation, current	4,900
Satellite performance incentives obligation, Noncurrent	22,200
ViaSat-1 and ViaSat-2 Satellites [Member] \| Satellite Performance Incentives Obligation [Member]
Long-term Purchase Commitment [Line Items]
Commitment amount	32,500
Future minimum payments under satellite performance incentives obligation for fiscal year 2022	5,300
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	5,500
Future minimum payments under satellite performance incentives obligation for fiscal year 2026	5,800
Future minimum payments under satellite performance incentives obligation thereafter	$ 5,600

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

Amount of purchase arrangement to be paid after fifth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

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- Definition

Amount of purchase arrangement to be paid in fifth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

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- Definition

Amount of purchase arrangement to be paid in fourth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

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- Definition

Amount of purchase arrangement to be paid in next fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

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- Definition

Amount of purchase arrangement to be paid in second fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

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- Definition

Amount of purchase arrangement to be paid in third fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

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- Definition

Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121559207&loc=d3e25336-109308

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- Definition

Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121559207&loc=d3e25336-109308

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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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