2.4.0.8011 - Disclosure - Note 4 - Income Taxestruefalsefalse1false falsefalsec8_From1Jan2013To30Jun2013http://www.sec.gov/CIK0001030749duration2013-01-01T00:00:002013-06-30T00:00:001true 1glf_IncomeTaxDisclosureTextBlockAbstractglf_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Income Tax Disclosure [Text Block]2false 2us-gaap_IncomeTaxDisclosureTextBlockus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00 (4)           INCOME TAXES Our estimated annual effective tax rate, adjusted for discrete tax items, is applied to interim periods’ pretax income (loss). We consider earnings of our foreign subsidiaries to be permanently reinvested, and as such, we have not provided for any U.S. federal or state income taxes on these permanently reinvested earnings. In recent years, we repatriated cash from our foreign subsidiaries current year foreign earnings and recognized U.S. tax expense, net of available credits, on those occasions. The incremental tax rate associated with these repatriations was approximately 30% with no U.S. cash tax requirement due to utilization of U.S. net operating losses. falsefalsefalsenonnum:textBlockItemTypenaThe entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph h -Article 4 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32639-109319 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32559-109319 false0Income Tax Disclosure [Text Block]falseNote 4 - Income TaxesUnKnownUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.gulfmark.com/role/Note4IncomeTaxes12