2.4.0.8041 - Disclosure - Note 8 - Fair Value Measurements (Details)truefalseIn Millions, unless otherwise specifiedfalse1false USDfalsefalse$c0_AsOf30Jun2013http://www.sec.gov/CIK0001030749instant2013-06-30T00:00:000001-01-01T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1true 1glf_FairValueDisclosuresTextBlockAbstractglf_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Disclosures [Text Block]2false 2us-gaap_DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateralus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse5000000.5USD$falsetruefalsexbrli:monetaryItemTypemonetaryFair value of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be offset against an obligation to return collateral under a master netting arrangement.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=20225523&loc=SL20225862-175312 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=7476318&loc=d3e41678-113959 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=28370219&loc=SL20226011-175313 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=28370219&loc=SL20226006-175313 false2Derivative Asset, Fair Value, Amount Not Offset Against CollateralfalseNote 8 - Fair Value Measurements (Details) (USD $)HundredThousandsUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.gulfmark.com/role/Note8FairValueMeasurementsDetails12