2.4.0.8400810 - Disclosure - Financial Instruments (Carrying amounts and fair value of the financial instruments) (Details)truefalseIn Thousands, unless otherwise specifiedfalse1false USDfalsefalse$AS_OF_Jun30_2013http://www.sec.gov/CIK0000075679instant2013-06-30T00:00:000001-01-01T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2false USDfalsefalse$AS_OF_Dec31_2012http://www.sec.gov/CIK0000075679instant2012-12-31T00:00:000001-01-01T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1true 2gciinc_CarryingValueDisclosuresAbstractgciinc_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Carrying Value Disclosures [Abstract]2false 3us-gaap_DebtAndCapitalLeaseObligationsus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse975675000975675USD$falsetruefalse2truefalsefalse957663000957663USD$falsetruefalsexbrli:monetaryItemTypemonetarySum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.13,16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 false2Current and Long-term Debt and Capital Lease Obligations3false 3us-gaap_OtherLiabilitiesus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse2589900025899falsefalsefalse2truefalsefalse2551100025511falsefalsefalsexbrli:monetaryItemTypemonetaryThe aggregate carrying amount, as of the balance sheet date, of liabilities not separately disclosed in the balance sheet.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 15 -Article 9 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.15) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 false2Other Liabilities4true 2us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Disclosure [Abstract]5false 3us-gaap_DebtInstrumentFairValueus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse963152000963152falsefalsefalse2truefalsefalse979594000979594falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13433-108611 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13476-108611 false2Current and Long-term Debt and Capital Lease Obligations, Fair Value Disclosure6false 3us-gaap_OtherLiabilitiesFairValueDisclosureus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse2506900025069USD$falsetruefalse2truefalsefalse2476600024766USD$falsetruefalsexbrli:monetaryItemTypemonetaryThis element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This element represents the fair value of liabilities categorized as other which are not in and of themselves material enough to require separate disclosure.No definition available.false2Other Liabilities, Fair Value DisclosurefalseFinancial Instruments (Carrying amounts and fair value of the financial instruments) (Details) (USD $)ThousandsUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.gci.net/role/FinancialInstrumentsCarryingAmountsAndFairValueOfTheFinancialInstrumentsDetails26