Number of persons employed by the Entity

No definition available.

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Namespace Prefix:	dei_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

- Definition

customers served

+ References

No definition available.

+ Details

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Namespace Prefix:	gwr_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of Provinces in which Entity Operates

+ References

No definition available.

+ Details

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Namespace Prefix:	gwr_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of Railroads Operated

+ References

No definition available.

+ Details

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Namespace Prefix:	gwr_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of Ports Operated

+ References

No definition available.

+ Details

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Namespace Prefix:	gwr_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Short Line and Regional Freight Railroad

+ References

No definition available.

+ Details

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Namespace Prefix:	gwr_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Track miles operated

+ References

No definition available.

+ Details

Name:	gwr_Trackmilesoperated
Namespace Prefix:	gwr_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13537-108611

+ Details

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

- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

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

- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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

- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

No definition available.

+ Details

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

- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of states the entity operates in as of the balance sheet date.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Details

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- Details

Name:	us-gaap_StatementGeographicalAxis=country_US
Namespace Prefix:
Data Type:	na
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- Details

Name:	us-gaap_StatementGeographicalAxis=country_CA
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementGeographicalAxis=us-gaap_NorthAmericaMember
Namespace Prefix:
Data Type:	na
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Period Type:

- Details

Name:	us-gaap_StatementGeographicalAxis=country_AU
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=gwr_NorthAmericanOperationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=gwr_MIRAMember
Namespace Prefix:
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Business and Customers (Details)	12 Months Ended
Business and Customers (Details)	Dec. 31, 2017 track_miles mile employee region railroad state port provinces customer reportable_segment	Dec. 31, 2016 region	Dec. 31, 2015
Number of railroads operated \| railroad	122
Number of operating regions \| region	9	10
Number of employees \| employee	8,000
Customers served \| customer	3,000
Number of reportable segments \| reportable_segment	3
Noncontrolling Interest, Ownership Percentage by Parent	51.10%
Ports operated \| port	40
Customer Concentration Risk [Member]
10 largest customers % of revenues	24.00%	22.00%	22.00%
United States [Member]
Number of States in which Entity Operates \| state	41
Canada [Member]
Number of Provinces in which Entity Operates \| provinces	4
North American [Member]
Short Line and Regional Freight Railroad \| railroad	115
Track miles \| mile	13,000
Australia [Member]
Track miles \| track_miles	1,400
North American Operations [Member]
Number of operating regions \| region	7
MIRA [Member]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	48.90%