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Capitalized interest as a percentage of inventory

No definition available.

Name:	grbk_CapitalizedInterestAsAPercentageOfInventory
Namespace Prefix:	grbk_
Data Type:	dtr-types1:percentItemType
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Carrying amount as of the balance sheet date of interest costs that were capitalized to properties under development during the land development and construction period of a project, and which are included in inventory.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 835
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483013/835-20-50-1

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Amount of interest cost charged to cost of sales that had been previously capitalized to inventory.

Name:	us-gaap_RealEstateInventoryCapitalizedInterestCostsCostOfSales1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

The amount of interest capitalized to an operative builder's inventory during the period.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.