The amount of unscheduled payments on debt applied to principal.

No definition available.

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Namespace Prefix:	gwr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of the required periodic payments applied to principal.

+ References

+ Details

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

- Definition

Amount of payment greater than the preceding installment payments to be paid at final maturity date of debt.

+ References

No definition available.

+ Details

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

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LoansPayableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gwr_UnitedStatesTermLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gwr_AustralianTermLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=gwr_UnitedKingdomTermLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
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- Details

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Long-Term Debt Amortization of Term Loans (Details) - 9 months ended Sep. 30, 2016 - Loans Payable [Member] £ in Thousands, AUD in Thousands, $ in Thousands	AUD	GBP (£)	USD ($)	GBP (£)	USD ($)
United States Term Loan [Member]
Prepayments of debt			$ 194,000
Principal amount of each quarterly installment			14,200
Principal payment upon maturity					$ 1,336,500
Long-term Debt, Gross					$ 1,578,000
Debt Instrument, Interest Rate, Stated Percentage	2.52%			2.52%	2.52%
Australian term loan [Member]
Prepayments of debt	AUD 30,400		22,800
Principal amount of each quarterly installment	4,100		3,100
Principal payment upon maturity \| AUD	178,028
Long-term Debt, Gross	AUD 255,127				$ 195,478
Debt Instrument, Interest Rate, Stated Percentage	3.67%			3.67%	3.67%
U.K. term loan [Member]
Prepayments of debt		£ 700	900
Principal amount of each quarterly installment		1,300	1,600
Principal payment upon maturity \| £				£ 75,532
Long-term Debt, Gross				£ 99,681	$ 129,296
Debt Instrument, Interest Rate, Stated Percentage	2.27%			2.27%	2.27%
Period 1 [Member] \| United States Term Loan [Member]
Principal amount of each quarterly installment			12,711
Period 1 [Member] \| Australian term loan [Member]
Principal amount of each quarterly installment \| AUD	AUD 4,058
Period 1 [Member] \| U.K. term loan [Member]
Principal amount of each quarterly installment \| £		1,271
Period 2 [Member] \| United States Term Loan [Member]
Principal amount of each quarterly installment			$ 25,421
Period 2 [Member] \| Australian term loan [Member]
Principal amount of each quarterly installment \| AUD	AUD 8,116
Period 2 [Member] \| U.K. term loan [Member]
Principal amount of each quarterly installment \| £		£ 2,542