Debt instrument extended maturity date.

No definition available.

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Period Type:	duration

- Definition

Line of credit facility default interest surcharge.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Line of credit facility, each quarter maximum availability commitment fee percentage.

+ References

No definition available.

+ Details

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- Definition

Line of credit facility, each quarter minimum availability commitment fee percentage.

+ References

No definition available.

+ Details

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- Definition

Line of credit facility, maximum borrowing capacity, percentage lesser of eligible in-transit inventory.

+ References

No definition available.

+ Details

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- Definition

Line of credit facility, maximum borrowing capacity, percentage lesser of eligible inventory.

+ References

No definition available.

+ Details

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- Definition

Line of credit facility, maximum borrowing capacity, percentage lesser of eligible net orderly liquidation value of in-transit inventory.

+ References

No definition available.

+ Details

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- Definition

Line of credit facility, maximum borrowing capacity, percentage lesser of eligible net orderly liquidation value of inventory.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Line of credit facility, maximum borrowing capacity, percentage of eligible accounts receivable.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Line of credit facility, maximum borrowing capacity, percentage of eligible credit card receivables.

+ References

No definition available.

+ Details

Name:	jill_LineOfCreditFacilityMaximumBorrowingCapacityPercentageOfEligibleCreditCardReceivables
Namespace Prefix:	jill_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of credit facility, maximum commitment fee percentage.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Line of credit facility, maximum in-transit periodic payment.

+ References

No definition available.

+ Details

Name:	jill_LineOfCreditFacilityMaximumInTransitPeriodicPayment
Namespace Prefix:	jill_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Line of credit facility, minimum commitment fee percentage.

+ References

No definition available.

+ Details

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Namespace Prefix:	jill_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of amortization expense attributable to debt issuance costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(8))
-URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1F
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 835
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-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=124435984&loc=d3e28555-108399

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
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

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
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-Paragraph 1
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-Section S99
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

+ Details

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

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
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Period Type:	duration

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Description of the frequency of the required periodic payments of interest, principal, or both, and the amount, if set, or a description of a formula upon which payment is based.

+ References

+ Details

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Period Type:	duration

- Definition

Description of the frequency of periodic payments, which may be presented in a variety of ways (for example, monthly, quarterly, annually).

+ References

+ Details

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- Definition

Description of interest rate for borrowing under credit facility. Includes, but is not limited to, terms and method for determining interest rate.

+ References

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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

- Details

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- Details

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- Details

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- Details

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Debt - Asset-Based Revolving Credit Agreement (Detail) - USD ($)		4 Months Ended	12 Months Ended			14 Months Ended	81 Months Ended
	May 08, 2015	Aug. 31, 2015	Jan. 29, 2022	Jan. 30, 2021	Feb. 01, 2020	Jul. 01, 2016	Jan. 29, 2022
Debt Instrument [Line Items]
Debt instrument, basis spread rate			5.00%
Debt Issuance cost			$ 2,500,000	$ 2,300,000	$ 1,500,000
ABL Facility [Member]
Debt Instrument [Line Items]
Debt instrument term	5 years
Total availability related to the facility	$ 40,000,000.0
Debt instrument, initial maturity date	May 08, 2020
Debt instrument extended maturity date	May 08, 2023
Credit facility maximum borrowing, percentage of eligible credit card receivables	90.00%
Credit facility maximum borrowing, percentage of eligible accounts receivables	85.00%
Credit facility maximum borrowing, percentage lesser of eligible inventory	100.00%
Credit facility maximum borrowing, percentage lesser of eligible net orderly liquidation value of inventory	90.00%
Credit facility maximum borrowing, percentage lesser of eligible in-transit inventory	100.00%
Credit facility maximum borrowing, percentage lesser of eligible net orderly liquidation value of in-transit inventory	90.00%
Credit facility, frequency of payment and payment terms	the in-transit maximum amount (the in-transit maximum amount is not to exceed $9.5 million during the first and third calendar quarters and $7.0 million during the second and fourth calendar quarters)
Credit facility, interest rate description			Interest on each LIBOR loan is payable on the last day of each interest period and no more than quarterly, and interest on each Base Rate loan is payable in arrears on the last business day of April, July, October and January. For both LIBOR and Base Rate loans, interest is payable periodically upon repayment, conversion or maturity, with interest periods ranging between 30 to 180 days at the election of the Company, or 12 months with the consent of all lenders.
Credit facility commitment fee						0.375%
Credit facility commitment fee, each calendar quarter historical excess availability is greater than 50%							0.375%
Credit facility commitment fee, each calendar quarter historical excess availability is less than or equal 50%							0.25%
Credit facility commitment fee, minimum each calendar quarter historical excess availability							50.00%
Credit facility commitment fee, maximum each calendar quarter historical excess availability							50.00%
Credit Facility drawn or outstanding			$ 0	11,100,000			$ 0
Credit Facility available borrowing capacity			22,600,000	23,800,000			$ 22,600,000
Interest expense			400,000	800,000	0
Debt Issuance cost			0	$ 100,000	$ 200,000
ABL Facility [Member] \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt instrument, basis spread rate	1.00%	2.00%
ABL Facility [Member] \| London Interbank Offered Rate (LIBOR) \| Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread rate							2.25%
ABL Facility [Member] \| London Interbank Offered Rate (LIBOR) \| Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread rate							2.50%
ABL Facility [Member] \| Federal Funds Effective Rate [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread rate	0.50%
ABL Facility [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread rate	2.00%	1.00%
ABL Facility [Member] \| Base Rate [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread rate							1.25%
ABL Facility [Member] \| Base Rate [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread rate							1.50%
ABL Facility [Member] \| 1st and 3rd Calendar Quarters [Member]
Debt Instrument [Line Items]
Credit facility maximum in-transit periodic payments	$ 9,500,000
Credit facility in-transit frequency of payments	quarters
ABL Facility [Member] \| 2nd and 4th Calendar Quarters [Member]
Debt Instrument [Line Items]
Credit facility maximum in-transit periodic payments	$ 7,000,000.0
Credit facility in-transit frequency of payments	quarters
Asset Based Revolving Credit Agreement [Member]
Debt Instrument [Line Items]
Total availability related to the facility			$ 22,600,000				$ 22,600,000
Debt instrument, initial maturity date			May 08, 2023
Credit facility default interest surcharge	2.00%