Number of additional shares reserved for issuance under an established employee stock purchase plan.

No definition available.

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- Definition

Annual increase in ordinary shares for available for future issuance.

+ References

No definition available.

+ Details

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- Definition

Annual increase in shares for available for future issuance by percentage of the outstanding ordinary shares on the first day of such fiscal year.

+ References

No definition available.

+ Details

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- Definition

Stock repurchase program authorization date.

+ References

No definition available.

+ Details

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Namespace Prefix:	amba_
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- Definition

Stock repurchase program, extended expiration date.

+ References

No definition available.

+ Details

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Namespace Prefix:	amba_
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- Definition

Stock repurchase program, extended expiration period.

+ References

No definition available.

+ Details

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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.

+ Details

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Data Type:	xbrli:stringItemType
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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644

+ Details

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Period Type:	instant

- Definition

The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

+ References

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

+ References

+ Details

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Period Type:	instant

- Definition

Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

+ References

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21463-112644

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
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-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Details

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Capital Stock - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended	9 Months Ended
	May 27, 2022	Apr. 30, 2022	Oct. 31, 2022	Jan. 31, 2022
Class Of Stock [Line Items]
Preference shares, shares authorized			20,000,000	20,000,000
Preference shares, par value			$ 0.00045	$ 0.00045
Preference shares, shares issued			0	0
Preference shares, shares outstanding			0	0
Ordinary shares, shares authorized			200,000,000	200,000,000
ESPP [Member]
Class Of Stock [Line Items]
Additional ordinary shares reserved for issuance		466,285
ESPP [Member] \| Scenario, plan automatically increased by the lessor of [Member]
Class Of Stock [Line Items]
Annual increase in ordinary shares for available for future issuance		1,500,000
Annual shares increase for future issuance by percentage under 2012 employee stock purchase plan		1.25%
Stock Repurchase Program [Member]
Class Of Stock [Line Items]
Stock repurchase program, authorization date	May 27, 2022
Stock repurchased, shares			0
Stock repurchase program, extended expiration period	12 months
Stock repurchase program, extended expiration date	Jun. 30, 2023
Amount available under stock repurchase program			$ 49.0