XML 101 R83.htm IDEA: XBRL DOCUMENT v3.24.0.1

INVENTORIES - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Inventory Disclosure [Abstract]
Lower of cost or net realizable value reserves	$ 9.2	$ 5.4
Reduction in inventory cost for interest received from manufacturers	7.0	2.8
Reduction in new vehicle cost of sales for interest assistance received related to vehicles sold	71.2	56.0	$ 54.2
Impairment of inventory	$ 3.4	$ 0.3	$ 0.1

X

- Definition

Manufacturer floorplan assistance recognized as reduction of cost of sales.

+ References

No definition available.

+ Details

Name:	gpi_ManufacturerFloorplanAssistanceRecognizedAsReductionOfCostOfSales
Namespace Prefix:	gpi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Manufacturer floorplan assistance recognized as reduction of inventory cost.

+ References

No definition available.

+ Details

Name:	gpi_ManufacturerFloorplanAssistanceRecognizedAsReductionOfInventoryCost
Namespace Prefix:	gpi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- References

No definition available.

+ Details

Name:	us-gaap_InventoryDisclosureAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount of valuation reserve for inventory.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(6))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB TOPIC 5.BB)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480581/330-10-S99-2

+ Details

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

X

- Definition

Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 330
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483080/330-10-50-2

+ Details

Name:	us-gaap_InventoryWriteDown
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration