Commitments and Contingencies and Other Items	9 Months Ended
Sep. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies and Other Items	Commitments and Contingencies and Other Items We are subject to various claims, legal proceedings and other contingent liabilities, including the matters described below, which individually or in the aggregate could materially affect our financial condition, future results of operations or cash flows. As a matter of course, we are prepared to both litigate these matters to judgment as needed, as well as to evaluate and consider reasonable settlement opportunities. Irrespective of its merits, litigation may be both lengthy and disruptive to our operations and could cause significant expenditure and diversion of management attention. We review our litigation accrual liabilities on a quarterly basis, but in accordance with applicable accounting guidelines only establish accrual liabilities when losses are deemed probable and reasonably estimable and only revise previously-established accrual liabilities when warranted by changes in circumstances, in each case based on then-available information. As such, as of any given date we could have exposure to losses under proceedings as to which no liability has been accrued or as to which the accrued liability is inadequate. Amounts accrued for our litigation contingencies at September 30, 2018 aggregated to approximately $138 million and are included in “Other” current liabilities and “Other Liabilities” in our consolidated balance sheet as of such date. 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 could have no effect on our results of operations but nonetheless could have an adverse effect on our cash flows. In this Note, when we refer to a class action as "putative" it is because a class has been alleged, but not certified in that matter. Shareholder Litigation CenturyLink and certain members of the CenturyLink Board of Directors have been named as defendants in a putative shareholder class action lawsuit filed on January 11, 2017 in the 4th Judicial District Court of the State of Louisiana, Ouachita Parish, captioned Jeffery Tomasulo v. CenturyLink, Inc., et al. The complaint asserts, among other things, that the members of CenturyLink’s Board allegedly breached their fiduciary duties to the CenturyLink shareholders in approving the Level 3 merger agreement and, more particularly, that: the consideration that CenturyLink agreed to pay to Level 3 stockholders in the transaction is allegedly unfairly high; the CenturyLink directors allegedly had conflicts of interest in negotiating and approving the transaction; and the disclosures set forth in our preliminary joint proxy statement/prospectus filed in December 2016 are insufficient in that they allegedly fail to contain material information concerning the transaction. The complaint seeks, among other things, a declaration that the members of the CenturyLink Board have breached their fiduciary duties, corrective disclosure, rescissory or other damages and equitable relief, including rescission of the transaction. On February 13, 2017, the parties entered into a memorandum of understanding providing for the settlement of the lawsuit. The proposed settlement is subject to court approval, among other conditions, and the amount of the settlement is not material to our consolidated financial statements. CenturyLink and certain CenturyLink board members and officers were named as defendants in a putative shareholder class action lawsuit filed on June 12, 2018 in the Boulder County District Court of the state of Colorado, captioned Houser et al. v. CenturyLink, et al. The complaint asserts claims on behalf of a putative class of former Level 3 shareholders who became CenturyLink shareholders as a result of the transaction. It alleges that the proxy statement provided to the Level 3 shareholders failed to disclose material information of several kinds, including information about strategic revenues, customer loss rates, and customer account issues, among other items. The complaint seeks damages, costs and fees, rescission, rescissory damages, and other equitable relief. Switched Access Disputes Subsidiaries of CenturyLink, Inc. are among hundreds of companies involved in an industry-wide dispute, raised in nearly 100 federal lawsuits (filed between 2014 and 2016) that have been consolidated as In Re: IntraMTA Switched Access Charges Litigation, in the United States District Court for the Northern District of Texas for pretrial procedures. The disputes relate to switched access charges that local exchange carriers ("LECs") collect from interexchange carriers ("IXCs") for IXCs' use of LEC's access services. In the lawsuits, various IXCs assert that LECs are prohibited from collecting access charges when IXCs exchange certain types of calls between mobile and wireline devices. Some of these IXCs seek refunds for access charges previously paid and declaratory relief from future access charges. In November 2015, the court rejected the IXCs' claims under federal law and entered final judgments against the IXCs on the LECs' claims for unpaid access charges and for late payment charges. The cases are now on appeal before the U.S. Court of Appeals for the Fifth Circuit. Separately, some of the defendants have petitioned the FCC to address these issues on an industry-wide basis. As both an IXC and a LEC, we both pay and assess significant amounts of the charges in question. The outcome of these disputes and lawsuits, as well as any related regulatory proceedings that could ensue, could affect our financial results and are currently not predictable. State Tax Suits Several Missouri municipalities have, beginning in May 2012, asserted claims alleging underpayment of taxes against CenturyLink, Inc. and several of its subsidiaries in a number of proceedings filed in the Circuit Court of St. Louis County, Missouri. These municipalities are seeking, among other things, declaratory relief regarding the application of business license and gross receipts taxes and back taxes from 2007 to the present, plus penalties and interest. In a February 2017 ruling in connection with one of these pending cases, the court entered an order awarding plaintiffs $4 million and broadening the tax base on a going-forward basis. We have appealed that ruling. In a June 2017 ruling in connection with another one of these pending cases, the court made findings which, if not overturned, will result in a tax liability to us well in excess of the contingent liability we have established. In due course, we plan to appeal that decision. We continue to vigorously defend against these claims. Billing Practices Suits In June 2017, a former employee filed an employment lawsuit against us claiming that she was wrongfully terminated for alleging that we charged some of our retail customers for products and services they did not authorize. Starting shortly thereafter and continuing since then, and based in part on the allegations made by the former employee, several legal proceedings have been filed. In June 2017, McLeod v. CenturyLink, a putative consumer class action, was filed against us in the U.S. District Court for the Central District of California alleging that we charged some of our retail customers for products and services they did not authorize. A number of other complaints asserting similar claims have been filed in other federal and state courts, as well. The lawsuits assert claims including fraud, unfair competition, and unjust enrichment. Also in June 2017, Craig. v. CenturyLink, Inc., et al., a putative securities investor class action, was filed in U.S. District Court for the Southern District of New York, alleging that we failed to disclose material information regarding improper sales practices, and asserting federal securities law claims. A number of other cases asserting similar claims have also been filed. Both the putative consumer class actions and the putative securities investor class actions have been transferred to the U.S. District Court for the District of Minnesota for coordinated and consolidated pretrial proceedings as In Re: CenturyLink Sales Practices and Securities Litigation. Beginning June 2017, we also received several shareholder derivative demands addressing related topics. In August 2017, the Board of Directors formed a special litigation committee of outside directors to address the allegations of impropriety contained in the shareholder derivative demands. In April 2018, the special litigation committee concluded its review of the derivative demands and declined to take further action. Since then, another demand has been received, and six derivative cases were filed. Two of these cases, Castagna v. Post and Pinsly v. Post, were filed in Louisiana state court in the Fourth Judicial District Court for the Parish of Ouachita; four others, Ault v. Post, Barbree v. Post, Flanders v. Post, and Palkon v. Boulet, were filed in Louisiana federal court in the Monroe Division of the Western District of Louisiana. These cases have been brought on behalf of CenturyLink against certain current and former officers and directors of the Company and seek damages for alleged breaches of fiduciary duties. In July 2017, the Minnesota state attorney general filed State of Minnesota v. CenturyTel Broadband Services LLC, et al. in the Asoka County Minnesota District Court, alleging claims of fraud and deceptive trade practices relating to improper consumer sales practices. The suit seeks an order of restitution on behalf of all CenturyLink customers, civil penalties, injunctive relief, and costs and fees. Additionally, we have received and responded to information requests and inquiries from other states. Peruvian Tax Litigation In 2005, the Peruvian tax authorities ("SUNAT") issued tax assessments against one of our Peruvian subsidiaries asserting $26 million, of additional income tax withholding and value-added taxes ("VAT"), penalties and interest for calendar years 2001 and 2002 on the basis that the Peruvian subsidiary incorrectly documented its importations. After taking into account the developments described below, as well as the accrued interest and foreign exchange effects, the total amount of exposure is $13 million at September 30, 2018. We challenged the assessments via administrative and then judicial review processes. In October 2011, the highest administrative review tribunal (the Tribunal) decided the central issue underlying the 2002 assessments in SUNAT's favor. We appealed the Tribunal's decision to the first judicial level, which decided the central issue in favor of Level 3. SUNAT and we filed cross-appeals with the court of appeal. In May 2017, the court of appeal issued a decision reversing the first judicial level. In June 2017, we filed an appeal of the decision to the Supreme Court of Justice, the final judicial level. Oral argument was held before the Supreme Court of Justice in October 2018. A decision on this case is pending. In October 2013, the Tribunal decided the central issue underlying the 2001 assessments in SUNAT’s favor. We appealed that decision to the first judicial level in Peru, which decided the central issue in favor of SUNAT. In June 2017, we filed an appeal with the court of appeal. In November 2017, the court of appeals issued a decision affirming the first judicial level and we filed an appeal of the decision to the Supreme Court of Justice. That appeal is pending. 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 of Level 3’s Latin American subsidiaries 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 Level 3 or termination of service relationships. Level 3 is vigorously defending itself against the asserted claims, which aggregate to approximately $30 million at September 30, 2018. Brazilian Tax Claims In December 2004, March 2009, April 2009 and July 2014, the São Paulo state tax authorities issued tax assessments against one of our Brazilian subsidiaries for the Tax on Distribution of Goods and Services (“ICMS”) with respect to revenue from leasing certain assets (in the case of the December 2004, March 2009 and July 2014 assessments) and revenue from the provision of Internet access services (in the case of the April 2009 and July 2014 assessments), 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. We have 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 September 2002, December 2004 and March 2009 assessments were rejected by the respective state administrative courts, and we have appealed those decisions to the judicial courts. In October 2012 and June 2014, we received favorable rulings from the lower court on the December 2004 and March 2009 assessments regarding equipment leasing, but those rulings are subject to appeal by the state. No ruling has been obtained with respect to the September 2002 assessment. The objections to the April and July 2009 and May 2012 assessments are still pending final administrative decisions. The July 2014 assessment was confirmed during the fourth quarter of 2014 at the first administrative level, and we appealed this decision to the second administrative level. We are vigorously contesting all such assessments in both states and, in particular, view the assessment of ICMS on revenue from equipment leasing to be without merit. These assessments, if upheld, could result in a loss of up to $34 million at September 30, 2018 in excess of the accruals established for these matters. Qui Tam Action Level 3 was notified in late 2017 of a qui tam action pending against Level 3 Communications, Inc. and others in the United States District Court for the Eastern District of Virginia, captioned United States of America ex rel., Stephen Bishop v. Level 3 Communications, Inc. et al. The original qui tam complaint was filed under seal on November 26, 2013, and an amended complaint was filed under seal on June 16, 2014. The court unsealed the complaints on October 26, 2017. The amended complaint alleges that Level 3, principally through two former employees, submitted false claims and made false statements to the government in connection with two government contracts. The relator seeks damages in this lawsuit of approximately $50 million, subject to trebling, plus statutory penalties, pre-and-post judgment interest, and attorney’s fees. The case is currently stayed. Level 3 is evaluating its defenses to the claims. At this time, Level 3 does not believe it is probable Level 3 will incur a material loss. If, contrary to its expectations, the plaintiff prevails in this matter and proves damages at or near $50 million, and is successful in having those damages trebled, the outcome could have a material adverse effect on our results of operations in the period in which a liability is recognized and on our cash flows for the period in which any damages are paid. Several people, including two former Level 3 employees were indicted in the United States District Court for the Eastern District of Virginia on October 3, 2017, and charged with, among other things, accepting kickbacks from a subcontractor, who was also indicted, for work to be performed under a prime government contract. Of the two former employees, one entered into a plea agreement, and the other is deceased. Level 3 is fully cooperating in the government’s investigations in this matter. Letters of Credit It is customary for us to use various financial instruments in the normal course of business. These instruments include letters of credit which are conditional commitments issued on our behalf in accordance with specified terms and conditions. As of September 30, 2018 and December 31, 2017, we had outstanding letters of credit or other similar obligations of approximately $129 million and $104 million, respectively. Other Proceedings, Disputes and Contingencies From time to time, we are involved in other proceedings incidental to our business, including patent infringement allegations, administrative hearings or proceedings of state public utility commissions relating primarily to our rates or services, actions relating to employee claims, various tax issues, environmental law issues, grievance hearings before labor regulatory agencies and miscellaneous third-party tort actions. We are currently defending several patent infringement lawsuits asserted against us by non-practicing entities, many of which are seeking substantial recoveries. These cases have progressed to various stages and one or more may go to trial in the coming 24 months if they are not otherwise resolved. Where applicable, we are seeking full or partial indemnification from our vendors and suppliers. As with all litigation, we are vigorously defending these actions and, as a matter of course, are prepared to litigate these matters to judgment, as well as to evaluate and consider all reasonable settlement opportunities. We are subject to various foreign, federal, state and local environmental protection and health and safety laws. From time to time, we are subject to judicial and administrative proceedings brought by various governmental authorities under these laws. Several such proceedings are currently pending, but none individually is reasonably expected to exceed $100,000 in fines and penalties. The outcome of these other proceedings is not predictable. However, based on current circumstances, we do not believe that the ultimate resolution of these other proceedings, after considering available defenses and any insurance coverage or indemnification rights, will have a material adverse effect on us. The matters listed above in this Note do not reflect all of our contingencies. For additional information on our contingencies, see Note 16 to the financial statements included in Item 8 of Part II of our annual report on Form 10-K for the year ended December 31, 2017. The ultimate outcome of the above-described matters may differ materially from the outcomes anticipated, estimated, projected or implied by us in certain of our statements appearing above in this Note, and proceedings currently viewed as immaterial by us may ultimately materially impact us.

Commitments and Contingencies and Other Items

We are subject to various claims, legal proceedings and other contingent liabilities, including the matters described below, which individually or in the aggregate could materially affect our financial condition, future results of operations or cash flows. As a matter of course, we are prepared to both litigate these matters to judgment as needed, as well as to evaluate and consider reasonable settlement opportunities.

Irrespective of its merits, litigation may be both lengthy and disruptive to our operations and could cause significant expenditure and diversion of management attention. We review our litigation accrual liabilities on a quarterly basis, but in accordance with applicable accounting guidelines only establish accrual liabilities when losses are deemed probable and reasonably estimable and only revise previously-established accrual liabilities when warranted by changes in circumstances, in each case based on then-available information. As such, as of any given date we could have exposure to losses under proceedings as to which no liability has been accrued or as to which the accrued liability is inadequate. Amounts accrued for our litigation contingencies at September 30, 2018 aggregated to approximately $138 million and are included in “Other” current liabilities and “Other Liabilities” in our consolidated balance sheet as of such date. 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 could have no effect on our results of operations but nonetheless could have an adverse effect on our cash flows.

In this Note, when we refer to a class action as "putative" it is because a class has been alleged, but not certified in that matter.

Shareholder Litigation

CenturyLink and certain members of the CenturyLink Board of Directors have been named as defendants in a putative shareholder class action lawsuit filed on January 11, 2017 in the 4th Judicial District Court of the State of Louisiana, Ouachita Parish, captioned Jeffery Tomasulo v. CenturyLink, Inc., et al. The complaint asserts, among other things, that the members of CenturyLink’s Board allegedly breached their fiduciary duties to the CenturyLink shareholders in approving the Level 3 merger agreement and, more particularly, that: the consideration that CenturyLink agreed to pay to Level 3 stockholders in the transaction is allegedly unfairly high; the CenturyLink directors allegedly had conflicts of interest in negotiating and approving the transaction; and the disclosures set forth in our preliminary joint proxy statement/prospectus filed in December 2016 are insufficient in that they allegedly fail to contain material information concerning the transaction. The complaint seeks, among other things, a declaration that the members of the CenturyLink Board have breached their fiduciary duties, corrective disclosure, rescissory or other damages and equitable relief, including rescission of the transaction. On February 13, 2017, the parties entered into a memorandum of understanding providing for the settlement of the lawsuit. The proposed settlement is subject to court approval, among other conditions, and the amount of the settlement is not material to our consolidated financial statements.

CenturyLink and certain CenturyLink board members and officers were named as defendants in a putative shareholder class action lawsuit filed on June 12, 2018 in the Boulder County District Court of the state of Colorado, captioned Houser et al. v. CenturyLink, et al. The complaint asserts claims on behalf of a putative class of former Level 3 shareholders who became CenturyLink shareholders as a result of the transaction. It alleges that the proxy statement provided to the Level 3 shareholders failed to disclose material information of several kinds, including information about strategic revenues, customer loss rates, and customer account issues, among other items. The complaint seeks damages, costs and fees, rescission, rescissory damages, and other equitable relief.

Switched Access Disputes

Subsidiaries of CenturyLink, Inc. are among hundreds of companies involved in an industry-wide dispute, raised in nearly 100 federal lawsuits (filed between 2014 and 2016) that have been consolidated as In Re: IntraMTA Switched Access Charges Litigation, in the United States District Court for the Northern District of Texas for pretrial procedures. The disputes relate to switched access charges that local exchange carriers ("LECs") collect from interexchange carriers ("IXCs") for IXCs' use of LEC's access services. In the lawsuits, various IXCs assert that LECs are prohibited from collecting access charges when IXCs exchange certain types of calls between mobile and wireline devices. Some of these IXCs seek refunds for access charges previously paid and declaratory relief from future access charges.

In November 2015, the court rejected the IXCs' claims under federal law and entered final judgments against the IXCs on the LECs' claims for unpaid access charges and for late payment charges. The cases are now on appeal before the U.S. Court of Appeals for the Fifth Circuit. Separately, some of the defendants have petitioned the FCC to address these issues on an industry-wide basis.

As both an IXC and a LEC, we both pay and assess significant amounts of the charges in question. The outcome of these disputes and lawsuits, as well as any related regulatory proceedings that could ensue, could affect our financial results and are currently not predictable.

State Tax Suits

Several Missouri municipalities have, beginning in May 2012, asserted claims alleging underpayment of taxes against CenturyLink, Inc. and several of its subsidiaries in a number of proceedings filed in the Circuit Court of St. Louis County, Missouri. These municipalities are seeking, among other things, declaratory relief regarding the application of business license and gross receipts taxes and back taxes from 2007 to the present, plus penalties and interest. In a February 2017 ruling in connection with one of these pending cases, the court entered an order awarding plaintiffs $4 million and broadening the tax base on a going-forward basis. We have appealed that ruling. In a June 2017 ruling in connection with another one of these pending cases, the court made findings which, if not overturned, will result in a tax liability to us well in excess of the contingent liability we have established. In due course, we plan to appeal that decision. We continue to vigorously defend against these claims.

Billing Practices Suits

In June 2017, a former employee filed an employment lawsuit against us claiming that she was wrongfully terminated for alleging that we charged some of our retail customers for products and services they did not authorize. Starting shortly thereafter and continuing since then, and based in part on the allegations made by the former employee, several legal proceedings have been filed.

In June 2017, McLeod v. CenturyLink, a putative consumer class action, was filed against us in the U.S. District Court for the Central District of California alleging that we charged some of our retail customers for products and services they did not authorize. A number of other complaints asserting similar claims have been filed in other federal and state courts, as well. The lawsuits assert claims including fraud, unfair competition, and unjust enrichment. Also in June 2017, Craig. v. CenturyLink, Inc., et al., a putative securities investor class action, was filed in U.S. District Court for the Southern District of New York, alleging that we failed to disclose material information regarding improper sales practices, and asserting federal securities law claims. A number of other cases asserting similar claims have also been filed. Both the putative consumer class actions and the putative securities investor class actions have been transferred to the U.S. District Court for the District of Minnesota for coordinated and consolidated pretrial proceedings as In Re: CenturyLink Sales Practices and Securities Litigation.

Beginning June 2017, we also received several shareholder derivative demands addressing related topics. In August 2017, the Board of Directors formed a special litigation committee of outside directors to address the allegations of impropriety contained in the shareholder derivative demands. In April 2018, the special litigation committee concluded its review of the derivative demands and declined to take further action. Since then, another demand has been received, and six derivative cases were filed. Two of these cases, Castagna v. Post and Pinsly v. Post, were filed in Louisiana state court in the Fourth Judicial District Court for the Parish of Ouachita; four others, Ault v. Post, Barbree v. Post, Flanders v. Post, and Palkon v. Boulet, were filed in Louisiana federal court in the Monroe Division of the Western District of Louisiana. These cases have been brought on behalf of CenturyLink against certain current and former officers and directors of the Company and seek damages for alleged breaches of fiduciary duties.

In July 2017, the Minnesota state attorney general filed State of Minnesota v. CenturyTel Broadband Services LLC, et al. in the Asoka County Minnesota District Court, alleging claims of fraud and deceptive trade practices relating to improper consumer sales practices. The suit seeks an order of restitution on behalf of all CenturyLink customers, civil penalties, injunctive relief, and costs and fees. Additionally, we have received and responded to information requests and inquiries from other states.

Peruvian Tax Litigation

In 2005, the Peruvian tax authorities ("SUNAT") issued tax assessments against one of our Peruvian subsidiaries asserting $26 million, of additional income tax withholding and value-added taxes ("VAT"), penalties and interest for calendar years 2001 and 2002 on the basis that the Peruvian subsidiary incorrectly documented its importations. After taking into account the developments described below, as well as the accrued interest and foreign exchange effects, the total amount of exposure is $13 million at September 30, 2018.

We challenged the assessments via administrative and then judicial review processes. In October 2011, the highest administrative review tribunal (the Tribunal) decided the central issue underlying the 2002 assessments in SUNAT's favor. We appealed the Tribunal's decision to the first judicial level, which decided the central issue in favor of Level 3. SUNAT and we filed cross-appeals with the court of appeal. In May 2017, the court of appeal issued a decision reversing the first judicial level. In June 2017, we filed an appeal of the decision to the Supreme Court of Justice, the final judicial level. Oral argument was held before the Supreme Court of Justice in October 2018. A decision on this case is pending.

In October 2013, the Tribunal decided the central issue underlying the 2001 assessments in SUNAT’s favor. We appealed that decision to the first judicial level in Peru, which decided the central issue in favor of SUNAT. In June 2017, we filed an appeal with the court of appeal. In November 2017, the court of appeals issued a decision affirming the first judicial level and we filed an appeal of the decision to the Supreme Court of Justice. That appeal is pending.

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 of Level 3’s Latin American subsidiaries 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 Level 3 or termination of service relationships. Level 3 is vigorously defending itself against the asserted claims, which aggregate to approximately $30 million at September 30, 2018.

Brazilian Tax Claims

In December 2004, March 2009, April 2009 and July 2014, the São Paulo state tax authorities issued tax assessments against one of our Brazilian subsidiaries for the Tax on Distribution of Goods and Services (“ICMS”) with respect to revenue from leasing certain assets (in the case of the December 2004, March 2009 and July 2014 assessments) and revenue from the provision of Internet access services (in the case of the April 2009 and July 2014 assessments), 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.

We have 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 September 2002, December 2004 and March 2009 assessments were rejected by the respective state administrative courts, and we have appealed those decisions to the judicial courts. In October 2012 and June 2014, we received favorable rulings from the lower court on the December 2004 and March 2009 assessments regarding equipment leasing, but those rulings are subject to appeal by the state. No ruling has been obtained with respect to the September 2002 assessment. The objections to the April and July 2009 and May 2012 assessments are still pending final administrative decisions. The July 2014 assessment was confirmed during the fourth quarter of 2014 at the first administrative level, and we appealed this decision to the second administrative level.

We are vigorously contesting all such assessments in both states and, in particular, view the assessment of ICMS on revenue from equipment leasing to be without merit. These assessments, if upheld, could result in a loss of up to $34 million at September 30, 2018 in excess of the accruals established for these matters.

Qui Tam Action

Level 3 was notified in late 2017 of a qui tam action pending against Level 3 Communications, Inc. and others in the United States District Court for the Eastern District of Virginia, captioned United States of America ex rel., Stephen Bishop v. Level 3 Communications, Inc. et al. The original qui tam complaint was filed under seal on November 26, 2013, and an amended complaint was filed under seal on June 16, 2014. The court unsealed the complaints on October 26, 2017.

The amended complaint alleges that Level 3, principally through two former employees, submitted false claims and made false statements to the government in connection with two government contracts. The relator seeks damages in this lawsuit of approximately $50 million, subject to trebling, plus statutory penalties, pre-and-post judgment interest, and attorney’s fees. The case is currently stayed.

Level 3 is evaluating its defenses to the claims. At this time, Level 3 does not believe it is probable Level 3 will incur a material loss. If, contrary to its expectations, the plaintiff prevails in this matter and proves damages at or near $50 million, and is successful in having those damages trebled, the outcome could have a material adverse effect on our results of operations in the period in which a liability is recognized and on our cash flows for the period in which any damages are paid.

Several people, including two former Level 3 employees were indicted in the United States District Court for the Eastern District of Virginia on October 3, 2017, and charged with, among other things, accepting kickbacks from a subcontractor, who was also indicted, for work to be performed under a prime government contract. Of the two former employees, one entered into a plea agreement, and the other is deceased. Level 3 is fully cooperating in the government’s investigations in this matter.

Letters of Credit

It is customary for us to use various financial instruments in the normal course of business. These instruments include letters of credit which are conditional commitments issued on our behalf in accordance with specified terms and conditions. As of September 30, 2018 and December 31, 2017, we had outstanding letters of credit or other similar obligations of approximately $129 million and $104 million, respectively.

Other Proceedings, Disputes and Contingencies

From time to time, we are involved in other proceedings incidental to our business, including patent infringement allegations, administrative hearings or proceedings of state public utility commissions relating primarily to our rates or services, actions relating to employee claims, various tax issues, environmental law issues, grievance hearings before labor regulatory agencies and miscellaneous third-party tort actions.

We are currently defending several patent infringement lawsuits asserted against us by non-practicing entities, many of which are seeking substantial recoveries. These cases have progressed to various stages and one or more may go to trial in the coming 24 months if they are not otherwise resolved. Where applicable, we are seeking full or partial indemnification from our vendors and suppliers. As with all litigation, we are vigorously defending these actions and, as a matter of course, are prepared to litigate these matters to judgment, as well as to evaluate and consider all reasonable settlement opportunities.

We are subject to various foreign, federal, state and local environmental protection and health and safety laws. From time to time, we are subject to judicial and administrative proceedings brought by various governmental authorities under these laws. Several such proceedings are currently pending, but none individually is reasonably expected to exceed $100,000 in fines and penalties.

The outcome of these other proceedings is not predictable. However, based on current circumstances, we do not believe that the ultimate resolution of these other proceedings, after considering available defenses and any insurance coverage or indemnification rights, will have a material adverse effect on us.

The matters listed above in this Note do not reflect all of our contingencies. For additional information on our contingencies, see Note 16 to the financial statements included in Item 8 of Part II of our annual report on Form 10-K for the year ended December 31, 2017. The ultimate outcome of the above-described matters may differ materially from the outcomes anticipated, estimated, projected or implied by us in certain of our statements appearing above in this Note, and proceedings currently viewed as immaterial by us may ultimately materially impact us.