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5us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantus-gaap_truenainstantfalsefalsefalsefalsefalsetruefalsefalseperiodStartLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse26290002629000falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:sharesItemTypesharesThe difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false3Balance outstanding at the end of the period (in dollars per share)28false 5us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePriceus-gaap_truenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse7.427.42USD$falsetruefalse2falsefalsefalse00falsefalsefalse3truefalsefalse7.427.42USD$falsetruefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalsenum:perShareItemTypedecimalAs of the balance sheet date, the weighted-average exercise price (at which grantees can acquire the shares reserved for issuance) for exercisable stock options that are fully vested or expected to vest.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph d(2) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false3Vested and expected to vest (in dollars per share)29false 5us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePriceus-gaap_truenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse8.078.07USD$falsetruefalse2falsefalsefalse00falsefalsefalse3truefalsefalse8.078.07USD$falsetruefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalsenum:perShareItemTypedecimalThe weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph b(1)(c) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Total intrinsic value of options exercised47false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse7false USDtruefalse$D2013Q2_RestrictedStockMemberhttp://www.sec.gov/CIK0001318568duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseRestricted stock, time-basedus-gaap_AwardTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_RestrictedStockMemberus-gaap_AwardTypeAxisexplicitMemberSharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Restricted stock, time-based48true 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false1Granted (in shares)56false 5us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse-42245-42245falsefalsefalse4truefalsefalse-84954-84954falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:sharesItemTypesharesThe number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph b(2)(d) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false1Vested (in shares)57false 5us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriodus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse-2000-2000falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:sharesItemTypesharesThe number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv)(3) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph b(2)(e) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false1Forfeited (in shares)58false 5us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumberus-gaap_truenainstantfalsefalsefalsefalsefalsefalsetruefalseperiodEndLabel1truefalsefalse437000437000falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse437000437000falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:sharesItemTypesharesThe number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph b(2)(b) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph b(2)(a) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false1Balance outstanding at the end of the period (in shares)59true 4us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Additional disclosures60false 5us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValueus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse100000100000USD$falsetruefalse2truefalsefalse300000300000USD$falsetruefalse3truefalsefalse300000300000USD$falsetruefalse4truefalsefalse600000600000USD$falsetruefalse5falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe total fair value of equity-based awards for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph c(2) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Total fair value of shares vestedfalseSHARE-BASED COMPENSATION (Details) (USD $)NoRoundingNoRoundingNoRoundingUnKnowntruefalsefalseSheethttp://www.gcainc.com/role/DisclosureShareBasedCompensationDetails560