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Data Type:	xbrli:monetaryItemType
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The amount of current notes and debentures issued and the current portion of non-current notes and debentures issued. [Refer: Notes and debentures issued]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2023-01-01
-Paragraph 112
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_112_c&doctype=Standard
-URIDate 2023-03-23

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Data Type:	xbrli:monetaryItemType
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Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

No definition available.

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The non-current portion of non-current notes and debentures issued. [Refer: Notes and debentures issued]

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The nominal or face amount of a financial instrument, used to calculate payments made on that instrument.

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Name:	ifrs-full_BorrowingsByNameAxis=grpu_UnsecuredDebentures3062PercentDueJune42027Member
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Name:	ifrs-full_BorrowingsByNameAxis=grpu_UnsecuredDebentures2194PercentDueAugust302028Member
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Name:	ifrs-full_BorrowingsByNameAxis=grpu_UnsecuredDebentures6074PercentDueApril122029Member
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Name:	ifrs-full_BorrowingsByNameAxis=grpu_UnsecuredDebentures2378PercentDueDecember182030Member
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Name:	ifrs-full_BorrowingsByNameAxis=grpu_TermLoanDueDecember192024Member
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Name:	ifrs-full_BorrowingsByNameAxis=grpu_TermLoanDueSeptember152025Member
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Name:	ifrs-full_BorrowingsByNameAxis=grpu_TermLoanDueSeptember82026Member
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