Coupon rate

No definition available.

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- Definition

Debt Instrument, Initial Principal Payment Per Unit

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Tangible Equity Units Issued During Period, TEUs, New Issues

+ References

No definition available.

+ Details

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- Definition

TEUs, Stated Amount, Per Unit Value

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- 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=34725769&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=6451184&loc=d3e28551-108399

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ 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(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount of the required periodic payments applied to principal.

+ 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

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

+ Details

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- Definition

Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=7655603&loc=d3e1448-109256

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Weighted-Average Number of Common Shares Outstanding
-URI http://asc.fasb.org/extlink&oid=6528421

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- Details

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Period Type:

- Details

Name:	us-gaap_StatementClassOfStockAxis=gwr_SettlementoftheprepaidstockpurchasecontractcomponentoftheTEUsMember
Namespace Prefix:
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Balance Type:
Period Type:

Long-term Debt TEUs (Details)		12 Months Ended
Long-term Debt TEUs (Details)	Sep. 19, 2012 USD ($) Tangible_Equty_Unit	Dec. 31, 2015 USD ($) shares	Dec. 31, 2014 shares	Dec. 31, 2013 shares	Jan. 01, 2013 USD ($)
Weighted average shares—Basic \| shares		56,734,000	55,305,000	53,788,000
TEUs - amortizing note [Member]
Company issued TEUs \| Tangible_Equty_Unit	2,300,000
Coupon rate	5.00%	5.00%	5.00%
Debt Instrument, Maturity date		Oct. 01, 2015
Principal amount per amortizing note	$ 14.1023
Tangible Equity Units Cash Installment Per Note		$ 1.25
Tangible Equity Units Initial Cash Installment					$ 1.4167
TEUs, Stated Amount, Per Unit Value	$ 100
Repayments of Debt		$ 2,800,000
Settlement of the prepaid stock purchase contract component of the TEUs [Member]
Weighted average shares—Basic \| shares		3,539,240	2,841,650	2,800,000