Revenue - Contract Liabilities - Refundable Customer Deposits (Details)	3 Months Ended
Mar. 31, 2022 USD ($)
Change in Contract with Customer, Liability
Average period to recognize contract with customer liability as revenue	19 months
Refundable Customer Deposits, Current
Change in Contract with Customer, Liability
Ending balance	$ 16.7
Refundable Customer Deposits
Change in Contract with Customer, Liability
Beginning balance	15,274,000
Additions to contract liabilities	7,891,000
Contract liabilities transferred to revenue	(6,479,000)
Ending balance	$ 16,686,000

Average period to recognize contract with customer liability as revenue.

No definition available.

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- Definition

Amount of increase in contract liability due to additions during the year.

+ References

No definition available.

+ Details

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

- References

No definition available.

+ Details

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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=123360276&loc=SL49130531-203044

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130549-203045

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=123360276&loc=SL49130532-203044

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130549-203045

+ Details

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Balance Type:	credit
Period Type:	duration

- Details

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- Details

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