Annual escalation percentage for lease term.

No definition available.

Name:	prts_AnnualEscalationPercentageForLeaseTerm
Namespace Prefix:	prts_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Operating leases monthly base rent commitment.

+ References

No definition available.

+ Details

Name:	prts_OperatingLeasesMonthlyBaseRentCommitment
Namespace Prefix:	prts_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Period under each renewal options.

+ References

No definition available.

+ Details

Name:	prts_PeriodUnderEachRenewalOptions
Namespace Prefix:	prts_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Sale Leaseback Transaction, Increase in Annual Rental Payments, Multiple of Change in Consumer Price Index

+ References

No definition available.

+ Details

Name:	prts_SaleLeasebackTransactionIncreaseinAnnualRentalPaymentsMultipleofChangeinConsumerPriceIndex
Namespace Prefix:	prts_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Sale Leaseback Transaction, Increase in Annual Rental Payments, Percentage

+ References

No definition available.

+ Details

Name:	prts_SaleLeasebackTransactionIncreaseinAnnualRentalPaymentsPercentage
Namespace Prefix:	prts_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Sale Leaseback Transaction, Lease Term

+ References

No definition available.

+ Details

Name:	prts_SaleLeasebackTransactionLeaseTerm
Namespace Prefix:	prts_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Sale lease initial term lease terms.

+ References

No definition available.

+ Details

Name:	prts_SaleLeaseInitialTermLeaseTerms
Namespace Prefix:	prts_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Sublease effective initial term on terminate sublease payment.

+ References

No definition available.

+ Details

Name:	prts_SubleaseEffectiveInitialTermOnTerminateSubleasePayment
Namespace Prefix:	prts_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Area of a real estate property.

+ References

No definition available.

+ Details

Name:	us-gaap_AreaOfRealEstateProperty
Namespace Prefix:	us-gaap_
Data Type:	num:areaItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

No definition available.

+ Details

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

- Definition

Date which lease or group of leases is set to expire, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

Name:	us-gaap_LeaseExpirationDate1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Term of the lessee's leasing arrangement renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_LesseeLeasingArrangementsOperatingLeasesRenewalTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Term of the lessee's leasing arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_LesseeLeasingArrangementsOperatingLeasesTermOfContract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the payments that the lessee is obligated to make or can be required to make in connection with a property under the terms of an agreement classified as an operating lease, excluding contingent rentals and a guarantee by the lessee of the lessor's debt and the lessee's obligation to pay (apart from the rental payments) executory costs such as insurance, maintenance, and taxes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41499-112717

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

-Section 55

-Paragraph 40

-Subparagraph (Note 3)

-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

-Section 25

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=7661868&loc=d3e34039-112682

+ Details

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

- Details

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

- Definition

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.13)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 13

-Subparagraph a

-Article 5

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 8

-Article 7

+ Details

Name:	us-gaap_PropertyPlantAndEquipmentNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

+ Details

Name:	us-gaap_PropertyPlantAndEquipmentUsefulLife
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The yearly payments due under the lease entered into in connection with the transaction involving the sale of property to another party and the lease of the property back to the seller.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6452660&loc=d3e36991-112694

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 40

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6456341&loc=d3e50796-112755

+ Details

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

- Definition

The date of the transaction involving the sale of the property to another party and the lease of the property back to the seller.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 40

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6456341&loc=d3e50796-112755

+ Details

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

- Definition

The amount of the gain recorded in connection with the transaction involving the sale of property to another party and the lease of the property back to the seller to be recognized in future periods.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 40

-Section 25

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6456126&loc=d3e49567-112750

+ Details

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

- Details

Name:	prts_LeaseArrangementTypeAxis=prts_SubleaseofOfficeBuildingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	prts_LeaseArrangementTypeAxis=prts_SubleaseofWarehouseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CounterpartyNameAxis=prts_NiaChloeLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CounterpartyNameAxis=prts_STOREMasterFundingIIILLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_AssetsHeldUnderCapitalLeasesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementGeographicalAxis=country_PH
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementGeographicalAxis=stpr_CA
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementGeographicalAxis=stpr_VA
Namespace Prefix:
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Period Type:

Commitments and Contingencies - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended			0 Months Ended		1 Months Ended	0 Months Ended
	Jan. 03, 2015	Dec. 28, 2013	Dec. 29, 2012	Apr. 17, 2013	Jul. 31, 2011	Dec. 31, 2008	Mar. 01, 2010	Nov. 01, 2011	Sep. 22, 2011 sqft
Other Commitments [Line Items]
Initial lease term	5 years
Facility rent expense	$ 1,895us-gaap_LeaseAndRentalExpense	$ 2,150us-gaap_LeaseAndRentalExpense	$ 2,388us-gaap_LeaseAndRentalExpense
Property and equipment	16,966us-gaap_PropertyPlantAndEquipmentNet	19,663us-gaap_PropertyPlantAndEquipmentNet
Capital Leased Assets (Facility)
Other Commitments [Line Items]
Estimated useful life of property and equipment	20 years			20 years
Property and equipment	8,736	9,253
Chesapeake, Virginia
Other Commitments [Line Items]
Lease expiration date	Jun. 30, 2016
Chesapeake, Virginia \| Warehouse
Other Commitments [Line Items]
Initial lease term						5 years
Lease expiration date					Jun. 30, 2016	Dec. 31, 2013
Base rent commitment	60
Philippines
Other Commitments [Line Items]
Initial lease term	63 months
Lease renewal term	60 months
Property and equipment	244	508
Philippines \| Commercial Office Space
Other Commitments [Line Items]
Lease renewal term							60 months
Monthly lease rent							25
Annual escalation, percentage							5.00%
Lease escalation beginning period							3 years
Carson, California \| Commercial Office Space
Other Commitments [Line Items]
Sublease initial term								60 months
Effective sublease initial term								42 months
Nia Chloe \| Sol Khazani
Other Commitments [Line Items]
Facility rent expense	378	374	374
STORE \| LaSalle, Illinois Facility
Other Commitments [Line Items]
Lease expiration date				Apr. 30, 2033
Purchase and sale agreement date				April 17, 2013
Period of lease under sale and lease back transaction				20 years
Initial base annual rent for first year				853
Percentage of annual increase in base rent				1.50%
Increased percentage in base rent with change in consumer price index				1.25
Excess of net proceeds over the net carrying value of capital leased asset under sale and lease back				376
STORE \| LaSalle, Illinois Facility \| Capital Leased Assets (Facility)
Other Commitments [Line Items]
Estimated useful life of property and equipment				20 years
Property and equipment	$ 8,736
Sublease of Office Building \| Carson, California
Other Commitments [Line Items]
Area of Real Estate Property									25,000
Sublease of Warehouse \| Chesapeake, Virginia
Other Commitments [Line Items]
Area of Real Estate Property					87,000