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v3.21.1

Organization and Other Matters - Additional Information (Detail) | 3 Months Ended
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Mar. 28, 2021 Shop Subsidiary JointVenture
Nature Of Business And Basis Of Presentation [Line Items] |
Number of shops franchisees operate | 45
Number of wholly owned subsidiaries | Subsidiary | 7
Number of joint ventures | JointVenture | 7
Minimum [Member] |
Nature Of Business And Basis Of Presentation [Line Items] |
Number of shops Potbelly Corporation owns or operates | 399
Ownership interest rate | 51.00%
Maximum [Member] |
Nature Of Business And Basis Of Presentation [Line Items] |
Ownership interest rate | 80.00%

X
- Definition Joint venture ownership percentage. + References No definition available. + Details
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X
- Definition Nature of business and basis of presentation. + References No definition available. + Details
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X
- Definition Number of joint ventures. + References No definition available. + Details
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X
- Definition Number of shops operate by franchisees. + References No definition available. + Details
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- Definition Number of shops owns or operates by entity. + References No definition available. + Details
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- Definition Number of wholly owned subsidiaries. + References No definition available. + Details
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Namespace Prefix: | pbpb_
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X
- Details
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Namespace Prefix: |
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Balance Type: |
Period Type: |

X
- Details
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Namespace Prefix: |
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Balance Type: |
Period Type: |