LOSS PER SHARE (Details) In Millions, unless otherwise specified	Sep. 30, 2012	Sep. 30, 2011
LOSS PER SHARE [Abstract]
Total shares outstanding under the Company's Share Lending Agreement	17.3	17.3

Total shares outstanding under the Company's Share Lending Agreement.

No definition available.

Name:	gsat_SharesOutstandingRelatingToCompanysShareLendingAgreement
Namespace Prefix:	gsat_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant