Commitments, Contingencies and Other Items	3 Months Ended
Mar. 31, 2013
Commitments and Contingencies Disclosure [Abstract]
Commitments, Contingencies and Other Items	Commitments, Contingencies and Other Items The Company is subject to various legal proceedings and other contingent liabilities that individually or in the aggregate could materially affect its financial condition, future results of operations or cash flows. Amounts accrued for such contingencies aggregate to $275 million and are included in “Other” current liabilities and “Other Liabilities” in the Company's consolidated balance sheet as at March 31, 2013. The establishment of an accrual does not mean that actual funds have been set aside to satisfy a given contingency. Thus, the resolution of a particular contingency for the amount accrued may have no effect on the Company's results of operations but could materially adversely affect its cash flows for the affected period. In accordance with the accounting guidance for contingencies, the Company accrues its estimate of a contingent liability when it is both probable that a liability has been incurred and the amount of the loss can be reasonably estimated. Where it is probable that a liability has been incurred and there is a range of expected loss for which no amount in the range is more likely than any other amount, the Company accrues at the low end of the range. The Company reviews its accruals at least quarterly and adjusts them to reflect the impact of negotiations, settlements, rulings, advice of legal counsel, and other information and events pertaining to a particular matter. Below is a description of material legal proceedings and other contingencies pending at March 31, 2013. Although the Company believes it has accrued for these matters in accordance with the accounting guidance for contingencies, contingencies are inherently unpredictable and it is possible that results of operations or cash flows could be materially and adversely affected in any particular period by unfavorable developments in, or resolution or disposition of, one or more of these matters. For those contingencies in respect of which the Company believes that it is reasonably possible that a loss may result that is materially in excess of the accrual (if any) established for the matter, the Company has below either provided an estimate of such possible loss or range of loss or included a statement that such an estimate cannot be made. In addition to the contingencies described below, the Company is party to many other legal proceedings and contingencies the resolution of which is not expected to materially affect its financial condition or future results of operations beyond the amounts accrued. Rights-of-Way Litigation The Company is party to a number of purported class action lawsuits involving its right to install fiber optic cable network in railroad right-of-ways adjacent to plaintiffs' land. In general, the Company obtained the rights to construct its networks from railroads, utilities, and others, and has installed its networks along the rights-of-way so granted. Plaintiffs in the purported class actions assert that they are the owners of lands over which the fiber optic cable networks pass, and that the railroads, utilities, and others who granted the Company the right to construct and maintain its network did not have the legal authority to do so. The complaints seek damages on theories of trespass, unjust enrichment and slander of title and property, as well as punitive damages. The Company has also received, and may in the future receive, claims and demands related to rights-of-way issues similar to the issues in these cases that may be based on similar or different legal theories. The Company has defeated motions for class certification in a number of these actions but expects that, absent settlement of these actions, plaintiffs in the pending lawsuits will continue to seek certification of statewide or multi-state classes. The only lawsuit in which a class was certified against the Company, absent an agreed upon settlement, occurred in Koyle, et. al. v. Level 3 Communications, Inc., et. al., a purported two state class action filed in the United States District Court for the District of Idaho. The Koyle lawsuit has been dismissed pursuant to a settlement reached in November 2010 as described further below. The Company negotiated a series of class settlements affecting all persons who own or owned land next to or near railroad rights of way in which it has installed its fiber optic cable networks. The United States District Court for the District of Massachusetts in Kingsborough v. Sprint Communications Co. L.P. granted preliminary approval of the proposed settlement; however, on September 10, 2009, the court denied a motion for final approval of the settlement on the basis that the court lacked subject matter jurisdiction and dismissed the case. In November 2010, the Company negotiated revised settlement terms for a series of state class settlements affecting all persons who own or owned land next to or near railroad rights of way in which the Company has installed its fiber optic cable networks. The Company is currently pursuing presentment of the settlement in applicable jurisdictions. The settlements, affecting current and former landowners, have received final federal court approval in multiple states and the parties are engaged in the claims process for those states. The settlement has also been presented to federal courts in additional states and approval is pending. Management believes that the Company has substantial defenses to the claims asserted in all of these actions and intends to defend them vigorously if a satisfactory settlement is not ultimately approved for all affected landowners. Peruvian Tax Litigation Beginning in 2005, one of the Company's Peruvian subsidiaries received a number of assessments for tax, penalty and interest for calendar years 2001 and 2002. Peruvian tax authorities (SUNAT) took the position that the Peruvian subsidiary incorrectly documented its importations resulting in additional income tax withholding and value-added taxes (VAT). The total amount of the asserted claims, including potential interest and penalties, was $26 million, consisting of $3 million for income tax withholding in connection with the import of services for calendar years 2001 and 2002, $7 million for VAT in connection with the import of services for calendar years 2001 and 2002, and $16 million in connection with the disallowance of VAT credits for periods beginning in 2005. Due to accrued interest and foreign exchange effects, and taking into account the developments described below, the total amount of exposure has increased to $96 million. The Company challenged the tax assessments during 2005 by filing administrative claims before SUNAT. During August 2006 and June 2007, SUNAT rejected the Company's administrative claims, thereby confirming the assessments. Appeals were filed in September 2006 and July 2007 in the Tax Court, which is the highest administrative authority. In October 2011, the Tax Court issued a ruling regarding VAT, associated penalties and penalties associated with withholding taxes, adjudicating the central issue underlying the assessments in the government's favor, while confirming the assessment in part and denying a portion of the assessment on procedural grounds. Other than an immaterial amount, all assessed items dismissed by the Tax Court in this ruling remain open for reassessment by SUNAT. While this Tax Court ruling applies only to 2002, the Company believes the Tax Court will issue a similar ruling with respect to 2001, and all material amounts likely to be waived due to procedural defects similarly remain open for reassessment. In November 2011, the Tax Court issued a ruling with respect to assessed 2001 withholding tax, holding that the statute of limitations had run prior to assessment by SUNAT. The Company believes that this adjudication of the withholding tax issue is likely to be final, and the Company expects to win a similar verdict with respect to assessed 2002 withholding tax. However, penalties with respect to withholding tax are not time-barred, and were confirmed in the Tax Court's October 2011 ruling. The Company has appealed the Tax Court's October 2011 decision to the judicial court in Peru. The Company has not received Tax Court rulings for all periods, but it has received adjudications of each substantive issue for at least one period. As a result, the Company expects decisions for the remaining open periods to be consistent with decisions already rendered. The Company intends to appeal any Tax Court verdict with respect to 2001 to the extent consistent with the October 2011 decision in the government's favor and will protest any reassessment of amounts dismissed by the Tax Court on procedural grounds. Employee Severance and Contractor Termination Disputes A number of former employees and third-party contractors have asserted a variety of claims in litigation against certain Latin American subsidiaries of the Company for separation pay, severance, commissions, pension benefits, unpaid vacation pay, breach of employment contracts, unpaid performance bonuses, property damages, moral damages and related statutory penalties, fines, costs and expenses (including accrued interest, attorneys fees and statutorily mandated inflation adjustments) as a result of their separation from the Company or termination of service relationships. The Company is vigorously defending itself against the asserted claims, which aggregate to approximately $40 million. Brazilian Tax Claims In December 2004, March 2009 and April 2009, the São Paulo state tax authorities issued tax assessments against one of the Company's Brazilian subsidiaries for the Tax on Distribution of Goods and Services (“ICMS”) with respect to revenues from leasing movable properties (in the case of the December 2004 and March 2009 assessments) and revenues from the provision of Internet access services (in the case of the April 2009 assessment), by treating such activities as the provision of communications services, to which the ICMS tax applies. In September 2002, July 2009 and May 2012, the Rio de Janeiro state tax authorities issued tax assessments to the same Brazilian subsidiary on similar issues. The Company has filed objections to these assessments, arguing that the lease of assets and the provision of Internet access are not communication services subject to ICMS. The objections to the December 2004 and September 2002 assessments were rejected by the respective state administrative courts, and the Company has appealed those decisions to the judicial courts. In October 2012, the Company received a favorable ruling from the lower court on the December 2004 assessment regarding equipment leasing, but that ruling is subject to appeal by the state. No ruling has been obtained with respect to the September 2002 assessment. The objections to the March, April and July 2009 and May 2012 assessments are still pending final administrative decisions. The Company is vigorously contesting all such assessments in both states, and in particular, views the assessment of ICMS on revenues from leasing movable properties to be without merit. Nevertheless, the Company believes that it is reasonably possible that these assessments could result in a loss of up to $61 million in excess of the accruals established for these matters. Letters of Credit It is customary for Level 3 to use various financial instruments in the normal course of business. These instruments include letters of credit. Letters of credit are conditional commitments issued on behalf of Level 3 in accordance with specified terms and conditions. As of March 31, 2013 and December 31, 2012, Level 3 had outstanding letters of credit or other similar obligations of approximately $27 million and $31 million, respectively, of which $25 million and $29 million, are collateralized by cash, that is reflected on the consolidated balance sheets as restricted cash. The Company does not believe it is reasonable to estimate the fair value of the letters of credit and does not believe exposure to loss is reasonably possible nor material.

Commitments, Contingencies and Other Items

The Company is subject to various legal proceedings and other contingent liabilities that individually or in the aggregate could materially affect its financial condition, future results of operations or cash flows. Amounts accrued for such contingencies aggregate to $275 million and are included in “Other” current liabilities and “Other Liabilities” in the Company's consolidated balance sheet as at March 31, 2013. The establishment of an accrual does not mean that actual funds have been set aside to satisfy a given contingency. Thus, the resolution of a particular contingency for the amount accrued may have no effect on the Company's results of operations but could materially adversely affect its cash flows for the affected period.

In accordance with the accounting guidance for contingencies, the Company accrues its estimate of a contingent liability when it is both probable that a liability has been incurred and the amount of the loss can be reasonably estimated. Where it is probable that a liability has been incurred and there is a range of expected loss for which no amount in the range is more likely than any other amount, the Company accrues at the low end of the range. The Company reviews its accruals at least quarterly and adjusts them to reflect the impact of negotiations, settlements, rulings, advice of legal counsel, and other information and events pertaining to a particular matter.

Below is a description of material legal proceedings and other contingencies pending at March 31, 2013. Although the Company believes it has accrued for these matters in accordance with the accounting guidance for contingencies, contingencies are inherently unpredictable and it is possible that results of operations or cash flows could be materially and adversely affected in any particular period by unfavorable developments in, or resolution or disposition of, one or more of these matters. For those contingencies in respect of which the Company believes that it is reasonably possible that a loss may result that is materially in excess of the accrual (if any) established for the matter, the Company has below either provided an estimate of such possible loss or range of loss or included a statement that such an estimate cannot be made. In addition to the contingencies described below, the Company is party to many other legal proceedings and contingencies the resolution of which is not expected to materially affect its financial condition or future results of operations beyond the amounts accrued.

Rights-of-Way Litigation

The Company is party to a number of purported class action lawsuits involving its right to install fiber optic cable network in railroad right-of-ways adjacent to plaintiffs' land. In general, the Company obtained the rights to construct its networks from railroads, utilities, and others, and has installed its networks along the rights-of-way so granted. Plaintiffs in the purported class actions assert that they are the owners of lands over which the fiber optic cable networks pass, and that the railroads, utilities, and others who granted the Company the right to construct and maintain its network did not have the legal authority to do so. The complaints seek damages on theories of trespass, unjust enrichment and slander of title and property, as well as punitive damages. The Company has also received, and may in the future receive, claims and demands related to rights-of-way issues similar to the issues in these cases that may be based on similar or different legal theories. The Company has defeated motions for class certification in a number of these actions but expects that, absent settlement of these actions, plaintiffs in the pending lawsuits will continue to seek certification of statewide or multi-state classes. The only lawsuit in which a class was certified against the Company, absent an agreed upon settlement, occurred in Koyle, et. al. v. Level 3 Communications, Inc., et. al., a purported two state class action filed in the United States District Court for the District of Idaho. The Koyle lawsuit has been dismissed pursuant to a settlement reached in November 2010 as described further below.

The Company negotiated a series of class settlements affecting all persons who own or owned land next to or near railroad rights of way in which it has installed its fiber optic cable networks. The United States District Court for the District of Massachusetts in Kingsborough v. Sprint Communications Co. L.P. granted preliminary approval of the proposed settlement; however, on September 10, 2009, the court denied a motion for final approval of the settlement on the basis that the court lacked subject matter jurisdiction and dismissed the case.

In November 2010, the Company negotiated revised settlement terms for a series of state class settlements affecting all persons who own or owned land next to or near railroad rights of way in which the Company has installed its fiber optic cable networks. The Company is currently pursuing presentment of the settlement in applicable jurisdictions. The settlements, affecting current and former landowners, have received final federal court approval in multiple states and the parties are engaged in the claims process for those states. The settlement has also been presented to federal courts in additional states and approval is pending.

Management believes that the Company has substantial defenses to the claims asserted in all of these actions and intends to defend them vigorously if a satisfactory settlement is not ultimately approved for all affected landowners.

Peruvian Tax Litigation

Beginning in 2005, one of the Company's Peruvian subsidiaries received a number of assessments for tax, penalty and interest for calendar years 2001 and 2002. Peruvian tax authorities (SUNAT) took the position that the Peruvian subsidiary incorrectly documented its importations resulting in additional income tax withholding and value-added taxes (VAT). The total amount of the asserted claims, including potential interest and penalties, was $26 million, consisting of $3 million for income tax withholding in connection with the import of services for calendar years 2001 and 2002, $7 million for VAT in connection with the import of services for calendar years 2001 and 2002, and $16 million in connection with the disallowance of VAT credits for periods beginning in 2005. Due to accrued interest and foreign exchange effects, and taking into account the developments described below, the total amount of exposure has increased to $96 million.

The Company challenged the tax assessments during 2005 by filing administrative claims before SUNAT. During August 2006 and June 2007, SUNAT rejected the Company's administrative claims, thereby confirming the assessments. Appeals were filed in September 2006 and July 2007 in the Tax Court, which is the highest administrative authority. In October 2011, the Tax Court issued a ruling regarding VAT, associated penalties and penalties associated with withholding taxes, adjudicating the central issue underlying the assessments in the government's favor, while confirming the assessment in part and denying a portion of the assessment on procedural grounds. Other than an immaterial amount, all assessed items dismissed by the Tax Court in this ruling remain open for reassessment by SUNAT. While this Tax Court ruling applies only to 2002, the Company believes the Tax Court will issue a similar ruling with respect to 2001, and all material amounts likely to be waived due to procedural defects similarly remain open for reassessment.

In November 2011, the Tax Court issued a ruling with respect to assessed 2001 withholding tax, holding that the statute of limitations had run prior to assessment by SUNAT. The Company believes that this adjudication of the withholding tax issue is likely to be final, and the Company expects to win a similar verdict with respect to assessed 2002 withholding tax. However, penalties with respect to withholding tax are not time-barred, and were confirmed in the Tax Court's October 2011 ruling.

The Company has appealed the Tax Court's October 2011 decision to the judicial court in Peru. The Company has not received Tax Court rulings for all periods, but it has received adjudications of each substantive issue for at least one period. As a result, the Company expects decisions for the remaining open periods to be consistent with decisions already rendered. The Company intends to appeal any Tax Court verdict with respect to 2001 to the extent consistent with the October 2011 decision in the government's favor and will protest any reassessment of amounts dismissed by the Tax Court on procedural grounds.

Employee Severance and Contractor Termination Disputes

A number of former employees and third-party contractors have asserted a variety of claims in litigation against certain Latin American subsidiaries of the Company for separation pay, severance, commissions, pension benefits, unpaid vacation pay, breach of employment contracts, unpaid performance bonuses, property damages, moral damages and related statutory penalties, fines, costs and expenses (including accrued interest, attorneys fees and statutorily mandated inflation adjustments) as a result of their separation from the Company or termination of service relationships. The Company is vigorously defending itself against the asserted claims, which aggregate to approximately $40 million.

Brazilian Tax Claims

In December 2004, March 2009 and April 2009, the São Paulo state tax authorities issued tax assessments against one of the Company's Brazilian subsidiaries for the Tax on Distribution of Goods and Services (“ICMS”) with respect to revenues from leasing movable properties (in the case of the December 2004 and March 2009 assessments) and revenues from the provision of Internet access services (in the case of the April 2009 assessment), by treating such activities as the provision of communications services, to which the ICMS tax applies. In September 2002, July 2009 and May 2012, the Rio de Janeiro state tax authorities issued tax assessments to the same Brazilian subsidiary on similar issues. The Company has filed objections to these assessments, arguing that the lease of assets and the provision of Internet access are not communication services subject to ICMS. The objections to the December 2004 and September 2002 assessments were rejected by the respective state administrative courts, and the Company has appealed those decisions to the judicial courts. In October 2012, the Company received a favorable ruling from the lower court on the December 2004 assessment regarding equipment leasing, but that ruling is subject to appeal by the state. No ruling has been obtained with respect to the September 2002 assessment. The objections to the March, April and July 2009 and May 2012 assessments are still pending final administrative decisions.

The Company is vigorously contesting all such assessments in both states, and in particular, views the assessment of ICMS on revenues from leasing movable properties to be without merit. Nevertheless, the Company believes that it is reasonably possible that these assessments could result in a loss of up to $61 million in excess of the accruals established for these matters.

Letters of Credit

It is customary for Level 3 to use various financial instruments in the normal course of business. These instruments include letters of credit. Letters of credit are conditional commitments issued on behalf of Level 3 in accordance with specified terms and conditions. As of March 31, 2013 and December 31, 2012, Level 3 had outstanding letters of credit or other similar obligations of approximately $27 million and $31 million, respectively, of which $25 million and $29 million, are collateralized by cash, that is reflected on the consolidated balance sheets as restricted cash. The Company does not believe it is reasonable to estimate the fair value of the letters of credit and does not believe exposure to loss is reasonably possible nor material.