Common shares issued to lenders.

No definition available.

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Balance Type:	na
Period Type:	duration

- Definition

Conversion of warrants into common share.

+ References

No definition available.

+ Details

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Namespace Prefix:	jill_
Data Type:	xbrli:sharesItemType
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- Definition

Warrants exercise price.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- 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

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of expense (income) related to adjustment to fair value of warrant liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section 25
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=109262497&loc=d3e20148-110875

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Amount of addition (reduction) to the amount at which a liability could be incurred (settled) in a current transaction between willing parties.

+ References

No definition available.

+ Details

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

- Definition

Value of shares of stock issued attributable to transactions classified as other.

+ References

No definition available.

+ Details

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

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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- Details

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- Details

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Subsequent Event - Additional Information (Detail) - USD ($) $ in Thousands		3 Months Ended
	May 31, 2021	May 01, 2021	Jan. 30, 2021
Subsequent Event [Line Items]
Principal amount of term loan		$ 4,992	$ 5,007
Fair value adjustment of derivative		(2,150)
Fair value adjustment of warrants - related party		18,646
Priming Term Loan Credit Agreement [Member]
Subsequent Event [Line Items]
Fair value adjustment of derivative		600
Fair value adjustment of warrants - related party		$ 38,300
Priming Term Loan Credit Agreement [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Common shares issued to lenders	272,097
Issuance of shares value	$ 4,600
Principal amount of term loan	$ 4,900
Penny Warrants \| Priming Term Loan Credit Agreement [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Conversion of warrants into common share	3,820,748
Warrants exercise price	$ 186