Derivatives - Narrative (Details) $ in Millions	1 Months Ended
Jun. 30, 2009 USD ($) contract	Dec. 31, 2013
8.00% Convertible Senior Notes Issued in 2013
Derivative [Line Items]
Loan interest rate		8.00%
Interest rate cap
Derivative [Line Items]
Number of Interest rate cap agreements (in contracts) \| contract	5
Maturity period	10 years
Interest rate cap \| Six-month LIBOR Rate
Derivative [Line Items]
Base rate to be capped, should the Base Rate not exceed 6.50%	5.50%
Interest on outstanding amounts on the Facility Agreement	6.50%
Base rate to be lowered from LIBOR, should the base rate exceed 6.50%	1.00%
Fee for interest rate cap agreements \| $	$ 12.4

Debt Instrument Basis Spread Reduction On Variable Rate

No definition available.

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Namespace Prefix:	gsat_
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- Definition

Debt Instrument Interest Base Rate

+ References

No definition available.

+ Details

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Namespace Prefix:	gsat_
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- Definition

Fee for interest rate cap agreements.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

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

+ 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)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

Cap rate on an interest rate derivative such as an interest rate cap or collar. If market rates exceed the cap rate, a payment or receipt is triggered on the contract.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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

- Definition

Number of interest rate derivative instruments held by the entity at the reporting date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5579245-113959

+ Details

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- Details

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- Details

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- Details

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