Capital Contribution From Shareholder Inducement to Convert Preferred Stock to Common Stock.

No definition available.

Name:	prch_CapitalContributionFromShareholderInducementToConvertPreferredStockToCommonStock
Namespace Prefix:	prch_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Cash contribution by related party to other shareholders.

+ References

No definition available.

+ Details

Name:	prch_MergerAgreementCashContributionRelatedParty
Namespace Prefix:	prch_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Number of shares contributed by related party to other shareholders.

+ References

No definition available.

+ Details

Name:	prch_MergerAgreementStockTransferredRelatedParty
Namespace Prefix:	prch_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of deferred acquisition cost payment for consideration paid monthly.

+ References

No definition available.

+ Details

Name:	prch_MinimumMonthlyPaymentDeferredAcquisitionAmount
Namespace Prefix:	prch_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of cash outflow for payment of deferred acquisition payments.

+ References

No definition available.

+ Details

Name:	prch_PaymentForBusinessAcquisitionDeferredAmount
Namespace Prefix:	prch_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of deferred acquisition cost payment for consideration paid quarterly.

+ References

No definition available.

+ Details

Name:	prch_QuarterlyPaymentDeferredAcquisitionAmount
Namespace Prefix:	prch_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=121583591&loc=d3e4332-108586

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=121583591&loc=d3e4304-108586

+ Details

Name:	us-gaap_DebtConversionConvertedInstrumentSharesIssued1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of warrants issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=121583591&loc=d3e4304-108586

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=121583591&loc=d3e4332-108586

+ Details

Name:	us-gaap_DebtConversionConvertedInstrumentWarrantsOrOptionsIssued1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Increase for accrued, but unpaid interest on the debt instrument for the period.

+ References

+ Details

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

- Definition

Carrying amount as of the balance sheet date of obligations due all related parties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.17)
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(3),(4))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

+ Details

Name:	us-gaap_DueToRelatedPartiesCurrentAndNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount for notes payable (written promise to pay), due to related parties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.17)
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

+ Details

Name:	us-gaap_NotesPayableRelatedPartiesCurrentAndNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The excess of (1) the fair value of all securities and other consideration transferred in transactions by the registrant to the holders of the convertible preferred stock over (2) the fair value of securities issuable pursuant to the original conversion terms, during the accounting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section S99
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=27010884&loc=d3e42851-122695

+ Details

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

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

- Definition

Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

No definition available.

+ Details

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

- Definition

Value of preferred stock and warrants for common stock issued.

+ References

No definition available.

+ Details

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

- Details

Name:	us-gaap_StatementClassOfStockAxis=prch_SeriesBRedeemableConvertiblePreferredStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=us-gaap_ConvertibleDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TypeOfArrangementAxis=prch_AcquisitionDeferralAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TypeOfArrangementAxis=prch_AmendedAcquisitionDeferralAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TypeOfArrangementAxis=prch_MergerAgreementWithProptechAcquisitionCorporationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=srt_ChiefExecutiveOfficerMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=us-gaap_InvestorMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=us-gaap_ImmediateFamilyMemberOfManagementOrPrincipalOwnerMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Related Parties (Details) - USD ($) $ in Thousands		1 Months Ended		9 Months Ended	12 Months Ended
Related Parties (Details) - USD ($) $ in Thousands	Dec. 19, 2019	Jul. 31, 2020	Jun. 30, 2019	Mar. 14, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Related Party Transaction [Line Items]
Induced conversion of preferred stock					$ 17,284
Amount borrowed	$ 3,000
Warrants to purchase	403,101
Series B Redeemable Convertible Preferred Stock
Related Party Transaction [Line Items]
Warrants to purchase						70,408
Series B Redeemable Convertible Preferred Stock \| Convertible Debt
Related Party Transaction [Line Items]
Aggregate original principal balance						$ 16,600
Accrued interest						$ 641
Debt conversion, converted instrument, shares issued						1,173,473
Existing agreement
Related Party Transaction [Line Items]
Acquisition deferral agreement							$ 931
Quarterly payment, deferred acquisition amount				$ 232
Amended agreement
Related Party Transaction [Line Items]
Minimum monthly payment, deferred acquisition amount			$ 100
Merger Agreement
Related Party Transaction [Line Items]
Induced conversion of preferred stock		$ 17,284
CEO
Related Party Transaction [Line Items]
Related party transaction, purchases from related party					2,873
CEO \| Convertible Debt
Related Party Transaction [Line Items]
Aggregate original principal balance						$ 1,000
CEO \| Merger Agreement
Related Party Transaction [Line Items]
Cash contribution by related party to other shareholders		$ 3,214
Number of shares contributed by related party to other shareholders		950,000
Capital contribution from shareholder inducement to convert preferred stock to common stock		$ 17,284
Investor \| Series B Redeemable Convertible Preferred Stock
Related Party Transaction [Line Items]
Debt conversion, converted instrument, shares issued						354,268
Warrants to purchase						21,256,000
Immediate family member of the companys CEO
Related Party Transaction [Line Items]
Debt conversion, converted instrument, shares issued							21,256
Warrants to purchase							2,042
Related party transaction, purchases from related party						$ 862
Due to related parties					$ 0	$ 2,693
Stock and warrants issued during Period, value, preferred stock and warrants							$ 500