Basis of Presentation and Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]
Use of Estimates	Use of Estimates Our consolidated financial statements are prepared in accordance with U.S. generally accepted accounting principles. These accounting principles require us to make certain estimates, judgments and assumptions. We believe that the estimates, judgments and assumptions we make when accounting for items and matters such as, but not limited to, investments, long-term contracts, customer retention patterns, allowance for doubtful accounts, depreciation, amortization, asset valuations, internal labor capitalization rates, recoverability of assets (including deferred tax assets), impairment assessments, pension, post-retirement and other post-employment benefits, taxes, certain liabilities and other provisions and contingencies are reasonable, based on information available at the time they were made. These estimates, judgments and assumptions can affect the reported amounts of assets, liabilities and components of stockholders' equity as of the dates of the consolidated balance sheets, as well as the reported amounts of revenue, expenses and components of cash flows during the periods presented in our consolidated statements of operations, our consolidated statements of comprehensive income (loss) and our consolidated statements of cash flows. We also make estimates in our assessments of potential losses in relation to threatened or pending tax and legal matters. See Note 12—Income Taxes and Note 15—Commitments and Contingencies for additional information. For matters not related to income taxes, if a loss is considered probable and the amount can be reasonably estimated, we recognize an expense for the estimated loss. If we have the potential to recover a portion of the estimated loss from a third party, we make a separate assessment of recoverability and reduce the estimated loss if recovery is also deemed probable. For matters related to income taxes, if the impact of an uncertain tax position is more likely than not to be sustained upon audit by the relevant taxing authority, then we recognize a benefit for the largest amount that is more likely than not to be sustained. No portion of an uncertain tax position will be recognized if the position has less than a 50% likelihood of being sustained. Interest is recognized on the amount of unrecognized benefit from uncertain tax positions. For all of these and other matters, actual results could differ from our estimates.
Revenue recognition	Revenue Recognition We recognize revenue for services when the related services are provided. Recognition of certain payments received in advance of services being provided is deferred until the service is provided. These advance payments include activation and installation charges, which we recognize as revenue over the expected customer relationship period, which ranges from eighteen months to over ten years depending on the service. We also defer costs for customer activations and installations. The deferral of customer activation and installation costs is limited to the amount of revenue deferred on advance payments. Costs in excess of advance payments are recorded as expense in the period such costs are incurred. Expected customer relationship periods are estimated using historical experience. Termination fees or other fees on existing contracts that are negotiated in conjunction with new contracts are deferred and recognized over the new contract term. We offer bundle discounts to our customers who receive certain groupings of services. These bundle discounts are recognized concurrently with the associated revenues and are allocated to the various services in the bundled offering based on the estimated selling price of services included in each bundled combination. Customer arrangements that include both equipment and services are evaluated to determine whether the elements are separable. If the elements are deemed separable and separate earnings processes exist, the revenue associated with the customer arrangement is allocated to each element based on the relative estimated selling price of the separate elements. We have estimated the selling prices of each element by reference to vendor-specific objective evidence of selling prices when the elements are sold separately. The revenue associated with each element is then recognized as earned. For example, if we receive an advance payment when we sell equipment and continuing service together, we immediately recognize as revenue the amount allocated to the equipment as long as all the conditions for revenue recognition have been satisfied. The portion of the advance payment allocated to the service based upon its relative selling price is recognized ratably over the longer of the contractual period or the expected customer relationship period. We periodically transfer optical capacity assets on our network to other telecommunications service carriers. These transactions are structured as indefeasible rights of use, commonly referred to as IRUs, which are the exclusive right to use a specified amount of capacity or fiber for a specified term, typically 20 years. We account for the cash consideration received on transfers of optical capacity assets and on all of the other elements deliverable under an IRU, as revenue ratably over the term of the agreement. We have not recognized revenue on any contemporaneous exchanges of our optical capacity assets for other optical capacity assets. In connection with offering products and services provided by third-party vendors, we review the relationship between us, the vendor and the end customer to assess whether revenue should be reported on a gross or net basis. In assessing whether revenue should be reported on a gross or net basis, we consider whether we act as a principal in the transaction, take title to the products, have risk and rewards of ownership or act as an agent or broker. Based on our agreements with DIRECTV and Verizon Wireless, we offer these services through sales agency relationships which are reported on a net basis. For our data hosting operations, we have service level commitments pursuant to contracts with certain of our clients. To the extent that such service levels are not achieved or are otherwise disputed due to performance or service issues or other service interruptions or conditions, we will estimate the amount of credits to be issued and record a reduction to revenue, with a corresponding increase in the credit reserve.
USF, Gross Receipts Taxes and Other Surcharges	USF, Gross Receipts Taxes and Other Surcharges In determining whether to include in our revenue and expenses the taxes and surcharges collected from customers and remitted to government authorities, including USF charges, sales, use, value added and some excise taxes, we assess, among other things, whether we are the primary obligor or principal taxpayer for the taxes assessed in each jurisdiction where we do business. In jurisdictions where we determine that we are the principal taxpayer, we record the surcharges on a gross basis and include them in our revenue and costs of services and products. In jurisdictions where we determine that we are merely a collection agent for the government authority, we record the taxes on a net basis and do not include them in our revenue and costs of services and products.
Advertising Costs	Advertising Costs Costs related to advertising are expensed as incurred and included in selling, general and administrative expenses in our consolidated statements of operations.
Legal Costs	Legal Costs In the normal course of our business, we incur costs to hire and retain external legal counsel to advise us on regulatory, litigation and other matters. We expense these costs as the related services are received.
Income Taxes	Income Taxes We file a consolidated federal income tax return with our eligible subsidiaries. The provision for income taxes consists of an amount for taxes currently payable, an amount for tax consequences deferred to future periods, adjustments to our liabilities for uncertain tax positions and amortization of investment tax credits. We record deferred income tax assets and liabilities reflecting future tax consequences attributable to tax net operating losses ("NOLs"), tax credit carryforwards and differences between the financial statement carrying value of assets and liabilities and the tax bases of those assets and liabilities. Deferred taxes are computed using enacted tax rates expected to apply in the year in which the differences are expected to affect taxable income. The effect on deferred income tax assets and liabilities of a change in tax rate is recognized in earnings in the period that includes the enactment date. We establish valuation allowances when necessary to reduce deferred income tax assets to the amounts that we believe are more likely than not to be recovered. A significant portion of our net deferred tax assets relate to tax benefits attributable to NOLs. Each quarter we evaluate the need to retain all or a portion of the valuation allowance on our deferred tax assets. See Note 12—Income Taxes for additional information.
Cash and Cash Equivalents	Cash and Cash Equivalents Cash and cash equivalents include highly liquid investments that are readily convertible into cash and are not subject to significant risk from fluctuations in interest rates. As a result, the value at which cash and cash equivalents are reported in our consolidated financial statements approximates their fair value. In evaluating investments for classification as cash equivalents, we require that individual securities have original maturities of ninety days or less and that individual investment funds have dollar-weighted average maturities of ninety days or less. To preserve capital and maintain liquidity, we invest with financial institutions we deem to be of sound financial condition and in high quality and relatively risk-free investment products. Our cash investment policy limits the concentration of investments with specific financial institutions or among certain products and includes criteria related to credit worthiness of any particular financial institution. Book overdrafts occur when checks have been issued but have not been presented to our controlled disbursement bank accounts for payment. Disbursement bank accounts allow us to delay funding of issued checks until the checks are presented for payment. Until the issued checks are presented for payment, the book overdrafts are included in accounts payable on our consolidated balance sheet. This activity is included in the operating activities section in our consolidated statements of cash flows.
Accounts Receivable and Allowance for Doubtful Accounts	Accounts Receivable and Allowance for Doubtful Accounts Accounts receivable are recognized based upon the amount due from customers for the services provided or at cost for purchased and other receivables less an allowance for doubtful accounts. The allowance for doubtful accounts receivable reflects our best estimate of probable losses inherent in our receivable portfolio determined on the basis of historical experience, specific allowances for known troubled accounts and other currently available evidence. We generally consider our accounts past due if they are outstanding over 30 days. Our collection process varies by the customer segment, amount of the receivable, and our evaluation of the customer's credit risk. Our past due accounts are written off against our allowance for doubtful accounts when collection is considered to be not probable. Any recoveries of accounts previously written off are generally recognized as a reduction in bad debt expense in the period received. The carrying value of accounts receivable net of the allowance for doubtful accounts approximates fair value.
Property, Plant and Equipment	Property, Plant and Equipment Property, plant and equipment acquired in connection with our acquisitions was recorded based on its estimated fair value as of its acquisition date plus the estimated value of any associated legally or contractually required retirement obligations. Purchased and constructed property, plant and equipment is recorded at cost, plus the estimated value of any associated legally or contractually required retirement obligations. Property, plant and equipment is depreciated primarily using the straight-line group method. Under the straight-line group method, assets dedicated to providing telecommunications services (which comprise the majority of our property, plant and equipment) that have similar physical characteristics, use and expected useful lives are categorized in the year acquired on the basis of equal life groups for purposes of depreciation and tracking. Generally, under the straight-line group method, when an asset is sold or retired in the course of normal business activities, the cost is deducted from property, plant and equipment and charged to accumulated depreciation without recognition of a gain or loss. A gain or loss is recognized in our consolidated statements of operations only if a disposal is abnormal or unusual. Leasehold improvements are amortized over the shorter of the useful lives of the assets or the expected lease term. Expenditures for maintenance and repairs are expensed as incurred. Interest is capitalized during the construction phase of network and other internal-use capital projects. Employee-related costs for construction of network and other internal use assets are also capitalized during the construction phase. Property, plant and equipment supplies used internally are carried at average cost, except for significant individual items for which cost is based on specific identification. We perform annual internal reviews to evaluate the reasonableness of the depreciable lives for our property, plant and equipment. Our reviews utilize models that take into account actual usage, physical wear and tear, replacement history, assumptions about technology evolution and, in certain instances, actuarially determined probabilities to estimate the remaining life of our asset base. We have asset retirement obligations associated with the legally or contractually required removal of a limited group of property, plant and equipment assets from leased properties and the disposal of certain hazardous materials present in our owned properties. When an asset retirement obligation is identified, usually in association with the acquisition of the asset, we record the fair value of the obligation as a liability. The fair value of the obligation is also capitalized as property, plant and equipment and then amortized over the estimated remaining useful life of the associated asset. Where the removal obligation is not legally binding, the net cost to remove assets is expensed in the period in which the costs are actually incurred. We review long-lived tangible assets for impairment whenever facts and circumstances indicate that the carrying amounts of the assets may not be recoverable. For assessment purposes, long-lived assets are grouped with other assets and liabilities at the lowest level for which identifiable cash flows are largely independent of the cash flows of other assets and liabilities, absent a material change in operations. An impairment loss is recognized only if the carrying amount of the asset group is not recoverable and exceeds its fair value. Recoverability of the asset group to be held and used is assessed by comparing the carrying amount of the asset group to the estimated undiscounted future net cash flows expected to be generated by the asset group. If the asset group's carrying value is not recoverable, an impairment charge is recognized for the amount by which the carrying amount of the asset group exceeds its fair value. We determine fair values by using a combination of comparable market values and discounted cash flows, as appropriate.
Goodwill, Customer Relationships and Other Intangible Assets	Goodwill, Customer Relationships and Other Intangible Assets Intangible assets arising from business combinations, such as goodwill, customer relationships, capitalized software, trademarks and trade names, are initially recorded at estimated fair value. We amortize customer relationships primarily over an estimated life of 10 years to 15, using either the sum-of-the-years-digits or the straight-line methods, depending on the type of customer. We amortize capitalized software using the straight-line method over estimated lives ranging up to seven years, except for approximately $237 million of our capitalized software costs, which represents costs to develop an integrated billing and customer care system which is amortized using the straight-line method over a 20 year period. We amortize our other intangible assets predominantly using the sum-of-the-years-digits method over an estimated life of four years. Other intangible assets not arising from business combinations are initially recorded at cost. Where there are no legal, regulatory, contractual or other factors that would reasonably limit the useful life of an intangible asset, we classify the intangible asset as indefinite-lived and such intangible assets are not amortized.
Pension and Post-Retirement Benefits	Pension and Post-Retirement Benefits We recognize the underfunded status of our defined benefit and post-retirement plans as an asset or a liability on our balance sheet. Each year's actuarial gains or losses are a component of our other comprehensive income (loss), which is then included in our accumulated other comprehensive loss. Pension and post-retirement benefit expenses are recognized over the period in which the employee renders service and becomes eligible to receive benefits. We make significant assumptions (including the discount rate, expected rate of return on plan assets and health care trend rates) in computing the pension and post-retirement benefits expense and obligations. See Note 8—Employee Benefits for additional information.
Foreign Currency	Foreign Currency Our results of operations include foreign subsidiaries, which are translated from the applicable functional currency to the United States Dollar using the average exchange rates during the reporting period, while assets and liabilities are translated at the reporting date. Resulting gains or losses from translating foreign currency are a component of our other comprehensive income (loss), which is then included in our accumulated other comprehensive loss.
Common Stock and Preferred Stock	Common Stock At December 31, 2013, we had unissued shares of CenturyLink common stock reserved of 31 million shares for incentive compensation, 4 million shares for acquisitions, 1 million shares for our dividend reinvestment plan and 1 million shares for our employee stock purchase plan ("ESPP"). Preferred stock Holders of outstanding CenturyLink preferred stock are entitled to receive cumulative dividends, receive preferential distributions equal to $25 per share plus unpaid dividends upon CenturyLink's liquidation and vote as a single class with the holders of common stock.