Amount of certified invoices included in accounts receivable that are in process of collection.

No definition available.

Name:	ppih_AccountsReceivableCertifiedInvoicesInProcessOfCollection
Namespace Prefix:	ppih_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the amount of accounts receivable, inclusive of retention receivables, that have been outstanding for several years as of the balance sheet date.

+ References

No definition available.

+ Details

Name:	ppih_AccountsReceivableOutstandingForSeveralYears
Namespace Prefix:	ppih_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the balance of the allowance for doubtful accounts pertaining to accounts receivable outstanding for several years.

+ References

No definition available.

+ Details

Name:	ppih_AllowanceForDoubtfulAccountsReceivableOutstandingForSeveralYears
Namespace Prefix:	ppih_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the number of major customers accounting for 10% or more of the specified concentration risk benchmark, which includes, but not limited to, sales revenue, accounts receivable, etc.

+ References

No definition available.

+ Details

Name:	ppih_NumberOfMajorCustomers
Namespace Prefix:	ppih_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the proceeds received during the period from the collection of accounts receivable that have been outstanding for several years.

+ References

No definition available.

+ Details

Name:	ppih_ProceedsFromCollectionOfAccountsReceivableOutstandingForSeveralYears
Namespace Prefix:	ppih_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the amount of retention receivable.

+ References

No definition available.

+ Details

Name:	ppih_RetentionReceivable
Namespace Prefix:	ppih_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e9054-108599

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13531-108611

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

+ Details

Name:	us-gaap_ConcentrationRiskPercentage1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_SalesRevenueNetMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConcentrationRiskByTypeAxis=us-gaap_CustomerConcentrationRiskMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_MajorCustomersAxis=ppih_OneCustomerMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_AccountsReceivableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BalanceSheetLocationAxis=us-gaap_OtherNoncurrentAssetsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Note 3 - Accounts Receivable (Details Textual) $ in Thousands	3 Months Ended			9 Months Ended		12 Months Ended
	Oct. 31, 2020 USD ($)	Apr. 30, 2020 USD ($)	Oct. 31, 2019	Oct. 31, 2020 USD ($)	Oct. 31, 2019	Jan. 31, 2020 USD ($)
Accounts Receivable, Outstanding for Several Years	$ 3,900			$ 3,900		$ 4,100
Retention Receivable	3,400			3,400
Accounts Receivable, Certified Invoices in Process of Collection		$ 500
Proceeds from Collection of Accounts Receivable Outstanding for Several Years	200
Allowance for Doubtful Accounts Receivable Outstanding for Several Years	$ 0			$ 0
Revenue Benchmark [Member] \| Customer Concentration Risk [Member]
Number of Major Customers	0		1	0	1
Revenue Benchmark [Member] \| Customer Concentration Risk [Member] \| One Customer [Member]
Concentration Risk, Percentage			16.00%		11.00%
Accounts Receivable [Member] \| Customer Concentration Risk [Member]
Number of Major Customers	1					1
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| One Customer [Member]
Concentration Risk, Percentage	10.10%					13.30%
Other Noncurrent Assets [Member]
Retention Receivable	$ 1,600			$ 1,600		$ 2,100