Common stock, shares, issued and outstanding.

No definition available.

Name:	prso_CommonStockSharesIssuedAndOutstanding
Namespace Prefix:	prso_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Escrow shares issued.

+ References

No definition available.

+ Details

Name:	prso_EscrowSharesIssued
Namespace Prefix:	prso_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Exchangeable shares issued.

+ References

No definition available.

+ Details

Name:	prso_ExchangeableSharesIssued
Namespace Prefix:	prso_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

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

- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ 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(29))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_CommonStockSharesIssued
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ 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 http://asc.fasb.org/extlink&oid=123467817&loc=d3e21463-112644

Reference 2: 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(29))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_CommonStockSharesOutstanding
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_CommonStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=prso_ExchangeableSharesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=prso_PerasoTechMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Business Combination - Schedule of Outstanding Shares of Common Stock (Details) - shares shares in Thousands	Dec. 31, 2021	Dec. 15, 2021	Dec. 31, 2020	Dec. 31, 2019
Business Acquisition [Line Items]
MoSys common stock outstanding prior to business combination	21,579	8,715,910	5,241
Common stock issued to Peraso Tech stockholders	21,579		5,241
Total shares issued and outstanding		21,569,158
Common Stock
Business Acquisition [Line Items]
Common stock issued to Peraso Tech stockholders	21,579		5,241	164
Escrow Shares - common stock		502,567
Exchangeable Shares
Business Acquisition [Line Items]
Escrow Shares - common stock		1,312,878
Peraso Tech
Business Acquisition [Line Items]
Common stock issued to Peraso Tech stockholders		3,055,584
Exchangeable Shares issued to Peraso Tech stockholders		7,982,219