XML 96 R81.htm IDEA: XBRL DOCUMENT
v3.6.0.2

Operating Leases (Details Textual) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($)
Operating Leases (Textual) [Abstract] |  |  |
Total term of lease facility | 30 years |  |
Initial term of lease facilities | 15 years |  |
Number of additional extensions on lease facility | 3 |  |
Extended period of lease under option | 5 years |  |
Future, non-cancelable sublease payments | $ 2.4 |  |
Total rent expense under all operating leases | $ 53.8 | $ 51.5 | $ 58.9

X
- Definition Extended period of lease under option. + References No definition available. + Details
Name: | gpi_ExtendedPeriodOfLeaseUnderOption
Namespace Prefix: | gpi_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Initial term of lease facilities + References No definition available. + Details
Name: | gpi_Initialtermofleasefacilities
Namespace Prefix: | gpi_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of additional extensions on lease facility + References No definition available. + Details
Name: | gpi_Numberofadditionalextensionsonleasefacility
Namespace Prefix: | gpi_
Data Type: | xbrli:pureItemType
Balance Type: | na
Period Type: | duration

X
- Definition Operating leases textual. + References No definition available. + Details
Name: | gpi_OperatingLeasesTextualAbstract
Namespace Prefix: | gpi_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Term of the lessee's leasing arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | us-gaap_LesseeLeasingArrangementsOperatingLeasesTermOfContract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Contractually required future rental payments receivable on noncancelable subleasing arrangements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717 + Details
Name: | us-gaap_OperatingLeasesFutureMinimumPaymentsDueFutureMinimumSubleaseRentals
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41499-112717 + Details
Name: | us-gaap_OperatingLeasesRentExpenseNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration