Number of shares of equity interests issued or issuable to acquire entity.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI https://asc.fasb.org/extlink&oid=126975305&loc=d3e6927-128479

+ Details

Name:	us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash outflow for cost incurred directly with the issuance of an equity security.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3291-108585

+ Details

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

- Definition

Cash received on stock transaction after deduction of issuance costs.

+ References

No definition available.

+ Details

Name:	us-gaap_SaleOfStockConsiderationReceivedOnTransaction
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of consideration received by subsidiary or equity investee in exchange for shares of stock issued or sold. Includes amount of cash received, fair value of noncash assets received, and fair value of liabilities assumed by the investor.

+ References

No definition available.

+ Details

Name:	us-gaap_SaleOfStockConsiderationReceivedPerTransaction
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

Name:	us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

+ Details

Name:	us-gaap_SaleOfStockPricePerShare
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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

- Details

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

- Details

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

- Details

Name:	us-gaap_SubsidiarySaleOfStockAxis=par_PublicOfferingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsidiarySaleOfStockAxis=us-gaap_PrivatePlacementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CounterpartyNameAxis=par_PARActIIILLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CounterpartyNameAxis=par_TRowePriceAssociatesIncMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Common Stock - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended			9 Months Ended
	Sep. 17, 2021	Apr. 08, 2021	Sep. 30, 2022	Sep. 30, 2021	Jun. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Subsequent Event [Line Items]
Payments for common stock issuance costs				$ 2,500	$ 4,300	$ 0	$ 6,827
Punchh Inc.
Subsequent Event [Line Items]
Equity interest issued (in shares)		1,493,130
MENU Technologies AG
Subsequent Event [Line Items]
Equity interest issued (in shares)			162,917
Public Offering
Subsequent Event [Line Items]
Number of shares issued in transaction (in shares)	982,143
Sale of stock (in dollars per share)	$ 56.00
Sale of stock, consideration received on transaction	$ 52,500
Private Placement
Subsequent Event [Line Items]
Number of shares issued in transaction (in shares)		2,352,942
Sale of stock, consideration received on transaction		$ 160,000
Payments for common stock issuance costs		$ 4,300
Private Placement \| PAR Act III, LLC
Subsequent Event [Line Items]
Number of shares issued in transaction (in shares)		73,530
Sale of stock (in dollars per share)		$ 68.00
Consideration received per transaction		$ 5,000
Private Placement \| T. Rowe Price Associates, Inc.
Subsequent Event [Line Items]
Number of shares issued in transaction (in shares)		2,279,412
Sale of stock (in dollars per share)		$ 68.00
Consideration received per transaction		$ 155,000