Applicable Margin, Commitment Fee Percentage

No definition available.

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- Definition

Description of minimum financial levels (for example, tangible net worth and working capital) and achievement of certain financial ratios (for example, working capital ratio and debt service coverage ratio), and adherence to certain clauses which generally require or restrict certain actions (for example, entering into a debt arrangement with equal or greater seniority, and selling or discontinuing a certain business segment or material subsidiary) to be in compliance with the covenant clauses of the debt agreement. May also include a discussion of the adverse consequences that would result if the entity violates or fails to satisfy the covenants.

+ 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 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ 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

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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

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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

- Definition

Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

+ References

+ Details

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

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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

- Definition

Percentage of an entity's outstanding debt that is designated as a hedged item in cash flow, fair value, or net investment hedge.

+ References

No definition available.

+ Details

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

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Balance Type:
Period Type:

- Details

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Balance Type:
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- Details

Name:	gwr_PeriodAxis=gwr_Period2Member
Namespace Prefix:
Data Type:	na
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- Details

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Balance Type:
Period Type:

- Details

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- Details

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Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_LetterOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementScenarioAxis=us-gaap_ScenarioForecastMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
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Data Type:	na
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- Details

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- Details

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Long-term Debt Australian Senior Credit Facility (Details) AUD in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2017 AUD	Dec. 31, 2017 USD ($)	Sep. 01, 2021	Dec. 01, 2019	Dec. 31, 2017 USD ($)	Dec. 31, 2016	Nov. 28, 2016 AUD	Nov. 28, 2016 USD ($)
Australia Credit Agreement
Debt Instrument, Face Amount							AUD 690,000	$ 511.4
Debt Instrument, Periodic Payment, Principal	AUD 18,000	$ 13.9
Debt Instrument, Interest Rate, Stated Percentage	4.28%				4.28%	4.64%
Applicable Margin, Commitment Fee Percentage	45.00%	45.00%
Revolving credit facility [Member]
Total available borrowing capacity \| $					$ 625.0
March 31, 2018 through December 31, 2019 \| Australia Credit Agreement
Debt Instrument, Periodic Payment, Principal	AUD 5,437
March 31, 2020 through December 31, 2021 \| Australia Credit Agreement
Debt Instrument, Periodic Payment, Principal	8,563
Maturity date - December 1, 2021 \| Australia Credit Agreement
Debt Instrument, Periodic Payment Terms, Balloon Payment to be Paid	AUD 560,000
December 31, 2018 \| Maximum Total Leverage Ratio [Member] \| Maximum [Member] \| Australia Credit Agreement
Debt Instrument, Covenant Description	4.75 to 1.00	4.75 to 1.00
January 1, 2019 through December 31, 2020 \| Maximum Total Leverage Ratio [Member] \| Maximum [Member] \| Australia Credit Agreement
Debt Instrument, Covenant Description	4.50 to 1.00	4.50 to 1.00
January 1, 2021 through December 31, 2021 \| Maximum Total Leverage Ratio [Member] \| Maximum [Member] \| Australia Credit Agreement
Debt Instrument, Covenant Description	4.25 to 1.00	4.25 to 1.00
Letter of Credit [Member] \| Australia Credit Agreement
Outstanding letter of credit guarantees	AUD 3,137
Revolving credit facility [Member] \| Australia Credit Agreement
Total available borrowing capacity	50,000						50,000	37.1
Unused borrowing capacity	AUD 46,863
Scenario, Forecast [Member] \| Australia Credit Agreement
Percentage of Debt Hedged by Interest Rate Derivatives			50.00%	75.00%
Australia Credit Agreement \| Minimum [Member]
Debt Instrument, Covenant Description	1.20 to 1.00	1.20 to 1.00
Australian Senior Credit Facility Tranche 1 [Member] \| Australia Credit Agreement
Debt Instrument, Face Amount							130,000	96.3
Australian Senior Credit Facility Tranche 1 [Member] \| Minimum [Member] \| Australia Credit Agreement
Debt Instrument, Interest Rate, Stated Percentage	2.35%				2.35%
Australian Senior Credit Facility Tranche 1 [Member] \| Maximum [Member] \| Australia Credit Agreement
Debt Instrument, Interest Rate, Stated Percentage	3.65%				3.65%
Australian Senior Credit Facility Tranche 2 [Member] \| Australia Credit Agreement
Debt Instrument, Face Amount							AUD 560,000	$ 415.0
Australian Senior Credit Facility Tranche 2 [Member] \| Minimum [Member] \| Australia Credit Agreement
Debt Instrument, Interest Rate, Stated Percentage	2.45%				2.45%
Australian Senior Credit Facility Tranche 2 [Member] \| Maximum [Member] \| Australia Credit Agreement
Debt Instrument, Interest Rate, Stated Percentage	3.75%				3.75%