Organization and Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Organization and Business	*Organization and Business* Noble Corporation plc, a public limited company incorporated under the laws of England and Wales (“Noble-UK”), is a leading offshore drilling contractor for the oil and gas industry. We perform contract drilling services with our fleet of mobile offshore drilling units located worldwide. As of the filing date of this Annual Report on Form 10-K, our fleet consisted of 15 jackups, nine drillships and eight semisubmersibles, including one high-specification, harsh environment jackup under construction. This excludes the semisubmersibles, Noble Driller, Noble Jim Thompson and Noble Paul Wolff. At December 31, 2014, our fleet was located in the United States, Brazil, Argentina, the North Sea, the Mediterranean, the Middle East, Asia and Australia. Noble and its predecessors have been engaged in the contract drilling of oil and gas wells since 1921. On November 20, 2013, pursuant to the Merger Agreement dated as of June 30, 2013 between Noble Corporation, a Swiss corporation (“Noble-Swiss”), and Noble-UK, Noble-Swiss merged with and into Noble-UK, with Noble-UK as the surviving company (the “Transaction”). In the Transaction, all of the outstanding ordinary shares of Noble-Swiss were cancelled, and Noble-UK issued, through an exchange agent, one ordinary share of Noble-UK in exchange for each ordinary share of Noble-Swiss. The Transaction effectively changed the place of incorporation of our publicly traded parent holding company from Switzerland to the United Kingdom. Noble Corporation, a Cayman Islands company (“Noble-Cayman”), is an indirect, wholly-owned subsidiary of Noble-UK, our publicly-traded parent company. Noble-UK’s principal asset is all of the shares of Noble-Cayman. Noble-Cayman has no public equity outstanding. The consolidated financial statements of Noble-UK include the accounts of Noble-Cayman, and Noble-UK conducts substantially all of its business through Noble-Cayman and its subsidiaries.
Principles of Consolidation	*Principles of Consolidation* The consolidated financial statements include our accounts, those of our wholly-owned subsidiaries and entities in which we hold a controlling financial interest. Our consolidated financial statements include the accounts of two joint ventures, in each of which we own a 50 percent interest. Our ownership interest meets the definition of variable interest under Financial Accounting Standards Board (“FASB”) codification and we have determined that we are the primary beneficiary. Intercompany balances and transactions have been eliminated in consolidation.
Foreign Currency Translation	*Foreign Currency Translation* Although we are a UK company, we define foreign currency as any non-U.S. denominated currency. In non-U.S. locations where the U.S. Dollar has been designated as the functional currency (based on an evaluation of factors including the markets in which the subsidiary operates, inflation, generation of cash flow, financing activities and intercompany arrangements), local currency transaction gains and losses are included in net income. In non-U.S. locations where the local currency is the functional currency, assets and liabilities are translated at the rates of exchange on the balance sheet date, while income statement items are translated at average rates of exchange during the year. The resulting gains or losses arising from the translation of accounts from the functional currency to the U.S. Dollar are included in “Accumulated other comprehensive loss” in the Consolidated Balance Sheets. We did not recognize any material gains or losses on foreign currency transactions or translations during the three years ended December 31, 2014.
Cash and Cash Equivalents	*Cash and Cash Equivalents* Cash and cash equivalents include cash on hand, demand deposits with banks and all highly liquid investments with original maturities of three months or less. Our cash, cash equivalents and short-term investments are subject to potential credit risk, and certain of our cash accounts carry balances greater than the federally insured limits. Cash and cash equivalents are primarily held by major banks or investment firms. Our cash management and investment policies restrict investments to lower risk, highly liquid securities and we perform periodic evaluations of the relative credit standing of the financial institutions with which we conduct business.
Property and Equipment	*Property and Equipment* Property and equipment is stated at cost, reduced by provisions to recognize economic impairment in value whenever events or changes in circumstances indicate an asset’s carrying value may not be recoverable. Major replacements and improvements are capitalized. When assets are sold, retired or otherwise disposed of, the cost and related accumulated depreciation are eliminated from the accounts and the gain or loss is recognized. Drilling equipment and facilities are depreciated using the straight-line method over their estimated useful lives as of the date placed in service or date of major refurbishment. Estimated useful lives of our drilling equipment range from three to thirty years. Other property and equipment is depreciated using the straight-line method over useful lives ranging from two to forty years. Included in accounts payable were $70 million and $88 million of capital accruals as of December 31, 2014 and 2013, respectively. Interest is capitalized on construction-in-progress using the weighted average cost of debt outstanding during the period of construction. Scheduled maintenance of equipment is performed based on the number of hours operated in accordance with our preventative maintenance program. Routine repair and maintenance costs are charged to expense as incurred; however, the costs of the overhauls and asset replacement projects that benefit future periods and which typically occur every three to five years are capitalized when incurred and depreciated over an equivalent period. These overhauls and asset replacement projects are included in “Drilling equipment and facilities” in Note 7. Such amounts, net of accumulated depreciation, totaled $179 million and $400 million at December 31, 2014 and 2013, respectively. Depreciation expense from continuing operations related to overhauls and asset replacement totaled $77 million, $70 million and $53 million for the years ended December 31, 2014, 2013 and 2012, respectively. We evaluate the impairment of property and equipment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. In addition, on an annual basis, we complete an impairment analysis on our rig fleet. An impairment loss on our property and equipment exists when the estimated undiscounted cash flows expected to result from the use of the asset and its eventual disposition are less than its carrying amount. Any impairment loss recognized represents the excess of the asset’s carrying value over the estimated fair value. As part of this analysis, we make assumptions and estimates regarding future market conditions. To the extent actual results do not meet our estimated assumptions, for a given rig class, we may take an impairment loss in the future. For additional information, see Note 11.
Goodwill	*Goodwill* We conduct impairment testing for our goodwill annually during the fourth quarter, and on an interim basis when an event occurs or circumstances change that indicate that the fair value of a reporting unit or the indefinite-lived intangible asset may have declined below its carrying value. We test goodwill at the reporting unit level, which is defined as an operating segment or one level below an operating segment that constitutes a business for which financial information is available and is regularly reviewed by management. Our goodwill is identified to one reporting unit Contract Drilling Services. Before testing goodwill, we consider whether or not to first assess qualitative factors to determine whether the existence of events or circumstances lead to a determination that it is more likely than not that the fair value of a reporting unit is less than its carrying amount and whether the two-step impairment test is required. If, as the result of our qualitative assessment, we determine that the two-step impairment test is required, or, alternatively, if we elect to forgo the qualitative assessment, we test goodwill for impairment by comparing the carrying amount of the reporting unit, to the fair value of the reporting unit utilizing both market and income evaluation methodologies. If this test suggests that the goodwill is not supportable, we proceed to the second step which compares the implied goodwill at the date of the test, to the book value of goodwill of the reporting unit. If the implied goodwill is lower than the book value of goodwill a write-down is taken to the implied value. For additional information, see Note 11.
Deferred Costs	*Deferred Costs* Deferred debt issuance costs are being amortized through interest expense over the life of the debt securities.
Insurance Reserves	*Insurance Reserves* We maintain various levels of self-insured retention for certain losses including property damage, loss of hire, employment practices liability, employers’ liability, and general liability, among others. We accrue for property damage and loss of hire charges on a per event basis. Employment practices liability claims are accrued based on actual claims during the year. Maritime employer’s liability claims are generally estimated using actuarial determinations. General liability claims are estimated by our internal claims department by evaluating the facts and circumstances of each claim (including incurred but not reported claims) and making estimates based upon historical experience with similar claims. At December 31, 2014 and 2013, loss reserves for personal injury and protection claims totaled $21 million and $29 million, respectively, and such amounts are included in “Other current liabilities” in the accompanying Consolidated Balance Sheets.
Revenue Recognition	*Revenue Recognition* Our typical dayrate drilling contracts require our performance of a variety of services for a specified period of time. We determine progress towards completion of the contract by measuring efforts expended and the cost of services required to perform under a drilling contract, as the basis for our revenue recognition. Revenues generated from our dayrate-basis drilling contracts and labor contracts are recognized on a per day basis as services are performed and begin upon the contract commencement, as defined under the specified drilling or labor contract. Dayrate revenues are typically earned, and contract drilling expenses are typically incurred ratably over the term of our drilling contracts. We review and monitor our performance under our drilling contracts to confirm the basis for our revenue recognition. Revenues from bonuses are recognized when earned, and when collectability is reasonably assured. In our dayrate drilling contracts, we typically receive compensation and incur costs for mobilization, equipment modification or other activities prior to the commencement of a contract. Any such compensation may be paid through a lump-sum payment or other daily compensation. Pre-contract compensation and costs are deferred until the contract commences. The deferred pre-contract compensation and costs are amortized, using the straight-line method, into income over the term of the initial contract period, regardless of the activity taking place. This approach is consistent with the economics for which the parties have contracted. Once a contract commences, we may conduct various activities, including drilling and well bore related activities, rig maintenance and equipment installation, movement between well locations or other activities. Deferred revenues from drilling contracts totaled $263 million and $303 million at December 31, 2014 and 2013, respectively. Such amounts are included in either “Other current liabilities” or “Other liabilities” in the accompanying Consolidated Balance Sheets, based upon our expected time of recognition. Related expenses deferred under drilling contracts totaled $94 million at December 31, 2014 as compared to $157 million at December 31, 2013, and are included in either “Other current assets” or “Other assets” in the accompanying Consolidated Balance Sheets, based upon our expected time of recognition. We record reimbursements from customers for “out-of-pocket” expenses as revenues and the related direct cost as operating expenses.
Income Taxes	*Income Taxes* Income taxes are based on the laws and rates in effect in the countries in which operations are conducted or in which we or our subsidiaries are considered resident for income tax purposes. In certain circumstances, we expect that, due to changing demands of the offshore drilling markets and the ability to redeploy our offshore drilling units, certain of such units will not reside in a location long enough to give rise to future tax consequences. As a result, no deferred tax asset or liability has been recognized in these circumstances. Should our expectations change regarding the length of time an offshore drilling unit will be used in a given location, we will adjust deferred taxes accordingly. We operate through various subsidiaries in numerous countries throughout the world, including the United States. Consequently, we are subject to changes in tax laws, treaties or regulations or the interpretation or enforcement thereof in the U.S., UK or jurisdictions in which we or any of our subsidiaries operate or are resident. Our income tax expense is based upon our interpretation of the tax laws in effect in various countries at the time that the expense was incurred. If the U.S. Internal Revenue Service (“IRS”) or other taxing authorities do not agree with our assessment of the effects of such laws, treaties and regulations, this could have a material adverse effect on us including the imposition of a higher effective tax rate on our worldwide earnings or a reclassification of the tax impact of our significant corporate restructuring transactions.
Earnings per Share	*Earnings per Share* Our unvested share-based payment awards, which contain non-forfeitable rights to dividends, are participating securities and are included in the computation of earnings per share pursuant to the “two-class” method. The “two-class” method allocates undistributed earnings between common shares and participating securities. The diluted earnings per share calculation under the “two-class” method also includes the dilutive effect of potential shares issued in connection with stock options. The dilutive effect of stock options is determined using the treasury stock method.
Share-Based Compensation Plans	*Share-Based Compensation Plans* We record the grant date fair value of share-based compensation arrangements as compensation cost using a straight-line method over the service period. Share-based compensation is expensed or capitalized based on the nature of the employee’s activities.
Certain Significant Estimates	*Certain Significant Estimates* The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (“GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amount of revenues and expenses during the reporting period. Certain accounting policies involve judgments and uncertainties to such an extent that there is reasonable likelihood that materially different amounts could have been reported under different conditions, or if different assumptions had been used. We evaluate our estimates and assumptions on a regular basis. We base our estimates on historical experience and various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates and assumptions used in preparation of our consolidated financial statements.
Reclassifications	*Reclassifications* Certain amounts in prior periods have been reclassified to conform to the current year presentation.
Accounting Pronouncements	*Accounting Pronouncements* In April 2014, the FASB issued Accounting Standards Update (“ASU”) No. 2014-08, which amends FASB Accounting Standards Codification (“ASC”) Topic 205, “Presentation of Financial Statements” and ASC Topic 360, “Property, Plant, and Equipment.” This ASU alters the definition of a discontinued operation to cover only asset disposals that are a strategic shift with a major effect on an entity’s operations and finances, and calls for more extensive disclosures about a discontinued operation’s assets, liabilities, income and expenses. The guidance is effective for all disposals, or classifications as held-for-sale, of components of an entity that occur within annual periods beginning on or after December 15, 2014. This standard was not early adopted in connection with the Spin-off. We are still evaluating what impact, if any, the adoption of this guidance will have on our financial condition, results of operations, cash flows or financial disclosures. In May 2014, the FASB issued ASU No. 2014-09, which amends ASC Topic 606, “Revenue from Contracts with Customers.” The amendments in this ASU are intended to provide a more robust framework for addressing revenue issues, improve comparability of revenue recognition practices and improve disclosure requirements. The amendments in this update are effective for interim and annual reporting periods beginning after December 15, 2016. We are still evaluating what impact, if any, the adoption of this guidance will have on our financial condition, results of operations, cash flows or financial disclosures. In June 2014, the FASB issued ASU No. 2014-12, which amends ASC Topic 718, “Compensation-Stock Compensation.” The guidance requires that a performance target that affects vesting and that could be achieved after the requisite service period be treated as a performance condition and should not be reflected in the estimate of the grant-date fair value of the award. The guidance is effective for annual periods beginning after December 15, 2015. The guidance can be applied prospectively for all awards granted or modified after the effective date or retrospectively to all awards with performance targets outstanding as of the beginning of the earliest annual period presented in the financial statements and to all new or modified awards thereafter. We are still evaluating what impact, if any, the adoption of this guidance will have on our financial condition, results of operations, cash flows or financial disclosures. In August 2014, the FASB issued ASU No. 2014-15, which amends ASC Subtopic 205-40, “Disclosure of Uncertainties about an Entity’s Ability to continue as a Going Concern.” The amendments in this ASU provide guidance related to management’s responsibility to evaluate whether there is substantial doubt about an entity’s ability to continue as a going concern and to provide related footnote disclosures. The amendments are effective for the annual period ending after December 15, 2016, and for annual periods and interim periods thereafter. We are still evaluating what impact, if any, the adoption of this guidance will have on our financial condition, results of operations, cash flows or financial disclosures. In January 2015, the FASB issued ASU No. 2015-01, which amends ASC Subtopic 225-20, “Income Statement – Extraordinary and Unusual Items.” The amendment in this ASU eliminates from GAAP the concept of extraordinary items. The amendments in this update are effective for interim and annual reporting periods beginning after December 15, 2015. We are still evaluating what impact, if any, the adoption of this guidance will have on our financial condition, results of operations, cash flows or financial disclosures. In February 2015, the FASB issued ASU No. 2015-02 which amends ASC Subtopic 810, “Consolidations.” This amendment affects reporting entities that are required to evaluate whether they should consolidate certain legal entities. Specifically, the amendments modify the evaluation of whether limited partnerships and similar legal entities are VIEs or voting interest entities; eliminate the presumption that a general partner should consolidate a limited partnership; affect the consolidation analysis of reporting entities that are involved with VIEs, particularly those that have fee arrangements and related party relationships. The standard is effective for interim and annual reporting periods beginning after December 15, 2015. The standard may be applied retrospectively or through a cumulative effect adjustment to retained earnings as of the beginning of the year of adoption. We are still evaluating what impact, if any, the adoption of this guidance will have on our financial condition, results of operations, cash flows or financial disclosures.