Commitments, Contingencies and Guarantees

12 Months Ended

Dec. 31, 2017

Commitments and Contingencies [Line Items]

Commitments, Contingencies and Guarantees

(a) Aircraft and Engine Purchase Commitments

Under all of our aircraft and engine purchase agreements, our total future commitments as of December 31, 2017 are expected to be as follows (approximately, in millions):



	2018		2019		2020		2021		2022		2023 and Thereafter		Total
Payments for aircraft commitments and certain engines ⁽¹⁾	$	1,826	$	2,730	$	2,730	$	2,858	$	2,138	$	1,482	$	13,764


⁽¹⁾	These amounts are net of purchase deposits currently held by the manufacturers and include all commitments for regional aircraft. American has granted a security interest in its purchase deposits with Boeing. Our purchase deposits held by all manufacturers totaled $1.2 billion as of December 31, 2017.

(b) Operating Leases and Other

We lease certain aircraft, engines and ground equipment, in addition to the majority of our ground facilities and terminal space. As of December 31, 2017, we had 421 aircraft under operating leases, with remaining terms ranging from three months to approximately 12 years. Airports are utilized for flight operations under lease arrangements with the municipalities or agencies owning or controlling such airports. Substantially all leases provide that the lessee must pay taxes, maintenance, insurance and certain other operating expenses applicable to the leased property. Some leases also include renewal and purchase options.

As of December 31, 2017, obligations under noncancellable operating leases for future minimum lease payments are as follows (approximately, in millions):



	2018		2019		2020		2021		2022		2023 and Thereafter		Total
Future minimum lease payments	$	2,195	$	1,974	$	1,784	$	1,339	$	1,159	$	3,266	$	11,717

Mainline and regional rent expense, excluding landing fees, was $2.8 billion in each of 2017, 2016 and 2015.

Additionally, we have purchase commitments related to jet fuel, facility construction projects and information technology support as follows (approximately): $2.0 billion in 2018, $1.4 billion in 2019, $890 million in 2020 and $950 million in 2021.

American has capacity purchase agreements with third-party regional carriers. The capacity purchase agreements provide that all revenues, including passenger, in-flight, ancillary, mail and freight revenues, go to American. In return, American agrees to pay predetermined fees to these airlines for operating an agreed-upon number of aircraft, without regard to the number of passengers on board. In addition, these agreements provide that American reimburses 100% of certain variable costs, such as airport landing fees and passenger liability insurance. American controls marketing, scheduling, ticketing, pricing and seat inventories.

As of December 31, 2017, American’s capacity purchase agreements with third-party regional carriers had expiration dates ranging from 2018 to 2027, with rights of American to extend the respective terms of certain agreements. See Part I, Item 2. Properties for unaudited information on the aircraft operated by third-party regional carriers under such capacity purchase agreements.

As of December 31, 2017, American’s minimum fixed obligations under its capacity purchase agreements with third-party regional carriers are as follows (approximately, in millions):



	2018		2019		2020		2021		2022		2023 and Thereafter		Total
Minimum fixed obligations under capacity purchase agreements with third-party regional carriers ⁽¹⁾	$	1,457	$	1,311	$	1,063	$	866	$	699	$	2,073	$	7,469

⁽¹⁾

Represents minimum payments under capacity purchase agreements with third-party regional carriers. These commitments are estimates of costs based on assumed minimum levels of flying under the capacity purchase agreements and American’s actual payments could differ materially. These obligations also include the portion of American’s future obligations representing the lease of aircraft for accounting purposes in the amount of approximately $377 million in 2018, $355 million in 2019, $320 million in 2020, $282 million in 2021, $239 million in 2022 and $699 million in 2023 and thereafter.

(d) Off-Balance Sheet Arrangements

Aircraft

American currently operates 387 owned aircraft and 113 leased aircraft which were financed with EETCs issued by pass-through trusts. These trusts are off-balance sheet entities, the primary purpose of which is to finance the acquisition of flight equipment. Rather than finance each aircraft separately when such aircraft is purchased, delivered or refinanced, these trusts allow American to raise the financing for a number of aircraft at one time and, if applicable, place such funds in escrow pending a future purchase, delivery or refinancing of the relevant aircraft. The trusts were also structured to provide for certain credit enhancements, such as liquidity facilities to cover certain interest payments, that reduce the risks to the purchasers of the trust certificates and, as a result, reduce the cost of aircraft financing to American.

Each trust covers a set number of aircraft scheduled to be delivered or refinanced upon the issuance of the EETC or within a specific period of time thereafter. At the time of each covered aircraft financing, the relevant trust used the proceeds of the issuance of the EETC (which may have been available at the time of issuance thereof or held in escrow until financing of the applicable aircraft following its delivery) to purchase equipment notes relating to the financed aircraft. The equipment notes are issued, at American’s election, in connection with a mortgage financing of the aircraft or, in certain cases, by a separate owner trust in connection with a leveraged lease financing of the aircraft. In the case of a leveraged lease financing, the owner trust then leases the aircraft to American. In both cases, the equipment notes are secured by a security interest in the aircraft. The pass-through trust certificates are not direct obligations of, nor are they guaranteed by, AAG or American. However, in the case of mortgage financings, the equipment notes issued to the trusts are direct obligations of American and, in certain instances, have been guaranteed by AAG. As of December 31, 2017, $11.9 billion associated with these mortgage financings is reflected as debt in the accompanying consolidated balance sheet.

With respect to leveraged leases, American evaluated whether the leases had characteristics of a variable interest entity. American concluded the leasing entities met the criteria for variable interest entities. American generally is not the primary beneficiary of the leasing entities if the lease terms are consistent with market terms at the inception of the lease and do not include a residual value guarantee, fixed-price purchase option or similar feature that obligates American to absorb decreases in value or entitles American to participate in increases in the value of the aircraft. American does not provide residual value guarantees to the bondholders or equity participants in the trusts. Some leases have a fair market value or a fixed price purchase option that allows American to purchase the aircraft at or near the end of the lease term. However, the option price approximates an estimate of the aircraft’s fair value at the option date. Under this feature, American does not participate in any increases in the value of the aircraft. American concluded it is not the primary beneficiary under these arrangements. Therefore, American accounts for the majority of its EETC leveraged lease financings as operating leases. American’s total future obligations to the trusts of each of the relevant EETCs under these leveraged lease financings are $572 million as of December 31, 2017, which are included in the future minimum lease payments table above.

Letters of Credit and Other

We provide financial assurance, such as letters of credit, surety bonds or restricted cash and investments, to primarily support projected workers’ compensation obligations and airport commitments. As of December 31, 2017, we had $448 million of letters of credit and surety bonds securing various obligations, of which $88 million is collateralized with our restricted cash. The letters of credit and surety bonds that are subject to expiration will expire on various dates through 2022.

(e) Legal Proceedings

Chapter 11 Cases. On November 29, 2011, AMR, American, and certain of AMR’s other direct and indirect domestic subsidiaries (the Debtors) filed voluntary petitions for relief under Chapter 11 of the United States Bankruptcy Code in the United States Bankruptcy Court for the Southern District of New York (the Bankruptcy Court). On October 21, 2013, the Bankruptcy Court entered an order approving and confirming the Debtors’ fourth amended joint plan of reorganization (as amended, the Plan). On the Effective Date, December 9, 2013, the Debtors consummated their reorganization pursuant to the Plan and completed the Merger.

Pursuant to rulings of the Bankruptcy Court, the Plan established the Disputed Claims Reserve to hold shares of AAG common stock reserved for issuance to disputed claimholders at the Effective Date that ultimately become holders of allowed claims. As of December 31, 2017, there were approximately 24.5 million shares of AAG common stock remaining in the Disputed Claims Reserve. As disputed claims are resolved, the claimants will receive distributions of shares from the Disputed Claims Reserve on the same basis as if such distributions had been made on or about the Effective Date. However, we are not required to distribute additional shares above the limits contemplated by the Plan, even if the shares remaining for distribution are not sufficient to fully pay any additional allowed unsecured claims. To the extent that any of the reserved shares remain undistributed upon resolution of all remaining disputed claims, such shares will not be returned to us but rather will be distributed to former AMR stockholders.

There is also pending in the Bankruptcy Court an adversary proceeding relating to an action brought by American to seek a determination that certain non-pension, postemployment benefits are not vested benefits and thus may be modified or terminated without liability to American. On April 18, 2014, the Bankruptcy Court granted American’s motion for summary judgment with respect to certain non-union employees, concluding that their benefits were not vested and could be terminated. The summary judgment motion was denied with respect to all other retirees. The Bankruptcy Court has not yet scheduled a trial on the merits concerning whether those retirees’ benefits are vested, and American cannot predict whether it will receive relief from obligations to provide benefits to any of those retirees. Our financial statements presently reflect these retirement programs without giving effect to any modification or termination of benefits that may ultimately be implemented based upon the outcome of this proceeding.

DOJ Antitrust Civil Investigative Demand. In June 2015, we received a Civil Investigative Demand (CID) from the United States Department of Justice (DOJ) as part of an investigation into whether there have been illegal agreements or coordination of air passenger capacity. The CID seeks documents and other information from us, and other airlines have announced that they have received similar requests. We are cooperating fully with the DOJ investigation.

Private Party Antitrust Action. Subsequent to announcement of the delivery of CIDs by the DOJ, we, along with Delta Air Lines, Inc., Southwest Airlines Co., United Airlines, Inc. and, in the case of litigation filed in Canada, Air Canada, have been named as defendants in approximately 100 putative class action lawsuits alleging unlawful agreements with respect to air passenger capacity, although Southwest has entered into a settlement with the plaintiffs that is pending approval by the court. The U.S. lawsuits have been consolidated in the Federal District Court for the District of Columbia. On October 28, 2016, the Court denied a motion by the airline defendants to dismiss all claims in the class actions. These lawsuits are in their relatively early stages and we intend to defend these matters vigorously.

Private Party Antitrust Action Related to the Merger. On July 2, 2013, a lawsuit captioned Carolyn Fjord, et al., v. US Airways Group, Inc., et al., was filed in the United States District Court for the Northern District of California. The complaint named as defendants US Airways Group and US Airways, Inc., alleged that the effect of the Merger may be to create a monopoly in violation of Section 7 of the Clayton Antitrust Act, and sought injunctive relief and/or divestiture. On August 6, 2013, the plaintiffs re-filed their complaint in the Bankruptcy Court, adding AMR and American as defendants. On November 27, 2013, the Bankruptcy Court denied plaintiffs’ motion to preliminarily enjoin the Merger. On May 12, 2017, defendants filed a motion for summary judgment. On June 23, 2017, plaintiffs filed an opposition to defendants’ motion and cross-motion for summary judgment. Briefing of the parties’ respective motions concluded on September 1, 2017; a hearing date has not yet been set. We believe this lawsuit is without merit and intend to vigorously defend against the allegations.

DOJ Investigation Related to the United States Postal Service. In April 2015, the DOJ informed us of an inquiry regarding American’s 2009 and 2011 contracts with the United States Postal Service for the international transportation of mail by air. In October 2015, we received a CID from the DOJ seeking certain information relating to these contracts and the DOJ has also sought information concerning certain of the airlines that transport mail on a codeshare basis. The DOJ has indicated it is investigating potential violations of the False Claims Act or other statutes. We are cooperating fully with the DOJ with regard to its investigation.

General. In addition to the specifically identified legal proceedings, we and our subsidiaries are also engaged in other legal proceedings from time to time. Legal proceedings can be complex and take many months, or even years, to reach resolution, with the final outcome depending on a number of variables, some of which are not within our control. Therefore, although we will vigorously defend ourselves in each of the actions described above and such other legal proceedings, their ultimate resolution and potential financial and other impacts on us are uncertain but could be material. See Part I, Item 1A. Risk Factors –“We may be a party to litigation in the normal course of business or otherwise, which could affect our financial position and liquidity” for unaudited additional discussion.

(f) Guarantees and Indemnifications

We are party to many routine contracts in which we provide general indemnities in the normal course of business to third parties for various risks. We are not able to estimate the potential amount of any liability resulting from the indemnities. These indemnities are discussed in the following paragraphs.

In our aircraft financing agreements, we generally indemnify the financing parties, trustees acting on their behalf and other relevant parties against liabilities (including certain taxes) resulting from the financing, manufacture, design, ownership, operation and maintenance of the aircraft regardless of whether these liabilities (or taxes) relate to the negligence of the indemnified parties.

Our loan agreements and other LIBOR-based financing transactions (including certain leveraged aircraft leases) generally obligate us to reimburse the applicable lender for incremental costs due to a change in law that imposes (i) any reserve or special deposit requirement against assets of, deposits with or credit extended by such lender related to the loan, (ii) any tax, duty or other charge with respect to the loan (except standard income tax) or (iii) capital adequacy requirements. In addition, our loan agreements and other financing arrangements typically contain a withholding tax provision that requires us to pay additional amounts to the applicable lender or other financing party, generally if withholding taxes are imposed on such lender or other financing party as a result of a change in the applicable tax law.

In certain transactions, including certain aircraft financing leases and loans, the lessors, lenders and/or other parties have rights to terminate the transaction based on changes in foreign tax law, illegality or certain other events or circumstances. In such a case, we may be required to make a lump sum payment to terminate the relevant transaction.

We have general indemnity clauses in many of our airport and other real estate leases where we as lessee indemnify the lessor (and related parties) against liabilities related to our use of the leased property. Generally, these indemnifications cover liabilities resulting from the negligence of the indemnified parties, but not liabilities resulting from the gross negligence or willful misconduct of the indemnified parties. In addition, we provide environmental indemnities in many of these leases for contamination related to our use of the leased property.

Under certain contracts with third parties, we indemnify the third-party against legal liability arising out of an action by the third-party, or certain other parties. The terms of these contracts vary and the potential exposure under these indemnities cannot be determined. We have liability insurance protecting us for some of the obligations we have undertaken under these indemnities.

American is required to make principal and interest payments for certain special facility revenue bonds issued by municipalities primarily to build or improve airport facilities and purchase equipment, which are leased to American. The payment of principal and interest of certain special facility revenue bonds is guaranteed by AAG. As of December 31, 2017, the remaining lease payments through 2035 guaranteeing the principal and interest on these bonds are $589 million, which are accounted for as operating leases.

As of December 31, 2017, AAG had issued guarantees covering approximately $810 million principal amount of American’s special facility revenue bonds (and interest thereon) and $8.5 billion principal amount of American’s secured debt (and interest thereon), including the Credit Facilities and certain EETC financings.

(g) Credit Card Processing Agreements

We have agreements with companies that process customer credit card transactions for the sale of air travel and other services. Our agreements allow these processing companies, under certain conditions, to hold an amount of our cash (referred to as a holdback) equal to a portion of advance ticket sales that have been processed by that company, but for which we have not yet provided the air transportation. Additional holdback requirements in the event of material adverse changes in our financial condition will reduce our liquidity in the form of unrestricted cash by the amount of the holdbacks. We are not currently required to maintain any holdbacks pursuant to these requirements.

(h) Labor Negotiations

As of December 31, 2017, we employed approximately 126,600 active full-time equivalent employees, of which 23,500 were employed by our regional operations. Approximately 85% of employees are covered by collective bargaining agreements with various labor unions. Negotiations for joint collective bargaining agreements covering our mainline maintenance, fleet service, stock clerks, maintenance control technicians and maintenance training instructors employees as well as for certain employee groups at our wholly-owned regional subsidiaries are continuing. There is no assurance that a successful or timely resolution of these labor negotiations will be achieved.

(i) Other

As a result of the terrorist attacks of September 11, 2001 and the subsequent liability protections provided for by the Air Transportation Safety and System Stabilization Act (the Stabilization Act), we recorded a liability for these terrorist attacks claims equal to the related insurance receivable due to us. The Stabilization Act provides that, notwithstanding any other provision of law, liability for all claims, whether compensatory or punitive, arising from these terrorist attacks, against any air carrier shall not exceed the liability coverage maintained by the air carrier. As of December 31, 2017, claims relating to this matter have been substantially resolved and the remaining liability and the amount of the offsetting receivable are not material.

American Airlines, Inc. [Member]

Commitments and Contingencies [Line Items]

Commitments, Contingencies and Guarantees

(a) Aircraft and Engine Purchase Commitments

Under all of American’s aircraft and engine purchase agreements, its total future commitments as of December 31, 2017 are expected to be as follows (approximately, in millions):



	2018		2019		2020		2021		2022		2023 and Thereafter		Total
Payments for aircraft commitments and certain engines ⁽¹⁾	$	1,826	$	2,730	$	2,730	$	2,858	$	2,138	$	1,482	$	13,764


⁽¹⁾	These amounts are net of purchase deposits currently held by the manufacturers and include all commitments for regional aircraft. American has granted a security interest in its purchase deposits with Boeing. American’s purchase deposits held by all manufacturers totaled $1.2 billion as of December 31, 2017.

(b) Operating Leases and Other

American leases certain aircraft, engines and ground equipment, in addition to the majority of its ground facilities and terminal space. As of December 31, 2017, American had 410 aircraft under operating leases, with remaining terms ranging from three months to approximately 12 years. Airports are utilized for flight operations under lease arrangements with the municipalities or agencies owning or controlling such airports. Substantially all leases provide that the lessee must pay taxes, maintenance, insurance and certain other operating expenses applicable to the leased property. Some leases also include renewal and purchase options.

As of December 31, 2017, obligations under noncancellable operating leases for future minimum lease payments are as follows (approximately, in millions):



	2018		2019		2020		2021		2022		2023 and Thereafter		Total
Future minimum lease payments	$	2,178	$	1,966	$	1,776	$	1,331	$	1,155	$	3,253	$	11,659

Mainline and regional rent expense, excluding landing fees, was $2.8 billion in 2017 and $2.7 billion in each of 2016 and 2015.

Additionally, American has purchase commitments related to jet fuel, facility construction projects and information technology support as follows (approximately): $2.0 billion in 2018, $1.4 billion in 2019, $890 million in 2020 and $950 million in 2021.

As of December 31, 2017, American’s minimum fixed obligations under its capacity purchase agreements with third-party regional carriers are as follows (approximately, in millions):



	2018		2019		2020		2021		2022		2023 and Thereafter		Total
Minimum fixed obligations under capacity purchase agreements with third-party regional carriers ⁽¹⁾	$	1,457	$	1,311	$	1,063	$	866	$	699	$	2,073	$	7,469

⁽¹⁾

(d) Off-Balance Sheet Arrangements

Aircraft

Letters of Credit and Other

American provides financial assurance, such as letters of credit, surety bonds or restricted cash and investments, to primarily support projected workers’ compensation obligations and airport commitments. As of December 31, 2017, American had $448 million of letters of credit and surety bonds securing various obligations, of which $88 million is collateralized with its restricted cash. The letters of credit and surety bonds that are subject to expiration will expire on various dates through 2022.

(e) Legal Proceedings

Pursuant to rulings of the Bankruptcy Court, the Plan established the Disputed Claims Reserve to hold shares of AAG common stock reserved for issuance to disputed claimholders at the Effective Date that ultimately become holders of allowed claims. As of December 31, 2017, there were approximately 24.5 million shares of AAG common stock remaining in the Disputed Claims Reserve. As disputed claims are resolved, the claimants will receive distributions of shares from the Disputed Claims Reserve on the same basis as if such distributions had been made on or about the Effective Date. However, American is not required to distribute additional shares above the limits contemplated by the Plan, even if the shares remaining for distribution are not sufficient to fully pay any additional allowed unsecured claims. To the extent that any of the reserved shares remain undistributed upon resolution of all remaining disputed claims, such shares will not be returned to American but rather will be distributed to former AMR stockholders.

There is also pending in the Bankruptcy Court an adversary proceeding relating to an action brought by American to seek a determination that certain non-pension, postemployment benefits are not vested benefits and thus may be modified or terminated without liability to American. On April 18, 2014, the Bankruptcy Court granted American’s motion for summary judgment with respect to certain non-union employees, concluding that their benefits were not vested and could be terminated. The summary judgment motion was denied with respect to all other retirees. The Bankruptcy Court has not yet scheduled a trial on the merits concerning whether those retirees’ benefits are vested, and American cannot predict whether it will receive relief from obligations to provide benefits to any of those retirees. American’s financial statements presently reflect these retirement programs without giving effect to any modification or termination of benefits that may ultimately be implemented based upon the outcome of this proceeding.

DOJ Antitrust Civil Investigative Demand. In June 2015, American received a Civil Investigative Demand (CID) from the United States Department of Justice (DOJ) as part of an investigation into whether there have been illegal agreements or coordination of air passenger capacity. The CID seeks documents and other information from American, and other airlines have announced that they have received similar requests. American is cooperating fully with the DOJ investigation.

Private Party Antitrust Action. Subsequent to announcement of the delivery of CIDs by the DOJ, American, along with Delta Air Lines, Inc., Southwest Airlines Co., United Airlines, Inc. and, in the case of litigation filed in Canada, Air Canada, have been named as defendants in approximately 100 putative class action lawsuits alleging unlawful agreements with respect to air passenger capacity, although Southwest has entered into a settlement with the plaintiffs that is pending approval by the court. The U.S. lawsuits have been consolidated in the Federal District Court for the District of Columbia. On October 28, 2016, the Court denied a motion by the airline defendants to dismiss all claims in the class actions. These lawsuits are in their relatively early stages and American intends to defend these matters vigorously.

Private Party Antitrust Action Related to the Merger. On July 2, 2013, a lawsuit captioned Carolyn Fjord, et al., v. US Airways Group, Inc., et al., was filed in the United States District Court for the Northern District of California. The complaint named as defendants US Airways Group and US Airways, Inc., alleged that the effect of the Merger may be to create a monopoly in violation of Section 7 of the Clayton Antitrust Act, and sought injunctive relief and/or divestiture. On August 6, 2013, the plaintiffs re-filed their complaint in the Bankruptcy Court, adding AMR and American as defendants. On November 27, 2013, the Bankruptcy Court denied plaintiffs’ motion to preliminarily enjoin the Merger. On May 12, 2017, defendants filed a motion for summary judgment. On June 23, 2017, plaintiffs filed an opposition to defendants’ motion and cross-motion for summary judgment. Briefing of the parties’ respective motions concluded on September 1, 2017; a hearing date has not yet been set. American believes this lawsuit is without merit and intends to vigorously defend against the allegations.

DOJ Investigation Related to the United States Postal Service. In April 2015, the DOJ informed American of an inquiry regarding American’s 2009 and 2011 contracts with the United States Postal Service for the international transportation of mail by air. In October 2015, American received a CID from the DOJ seeking certain information relating to these contracts and the DOJ has also sought information concerning certain of the airlines that transport mail on a codeshare basis. The DOJ has indicated it is investigating potential violations of the False Claims Act or other statutes. American is cooperating fully with the DOJ with regard to its investigation.

General. In addition to the specifically identified legal proceedings, American and its subsidiaries are also engaged in other legal proceedings from time to time. Legal proceedings can be complex and take many months, or even years, to reach resolution, with the final outcome depending on a number of variables, some of which are not within American’s control. Therefore, although American will vigorously defend itself in each of the actions described above and such other legal proceedings, their ultimate resolution and potential financial and other impacts on American are uncertain but could be material. See Part I, Item 1A. Risk Factors –“We may be a party to litigation in the normal course of business or otherwise, which could affect our financial position and liquidity” for unaudited additional discussion.

(f) Guarantees and Indemnifications

American is a party to many routine contracts in which it provides general indemnities in the normal course of business to third parties for various risks. American is not able to estimate the potential amount of any liability resulting from the indemnities. These indemnities are discussed in the following paragraphs.

In its aircraft financing agreements, American generally indemnifies the financing parties, trustees acting on their behalf and other relevant parties against liabilities (including certain taxes) resulting from the financing, manufacture, design, ownership, operation and maintenance of the aircraft regardless of whether these liabilities (or taxes) relate to the negligence of the indemnified parties.

American’s loan agreements and other LIBOR-based financing transactions (including certain leveraged aircraft leases) generally obligate American to reimburse the applicable lender for incremental costs due to a change in law that imposes (i) any reserve or special deposit requirement against assets of, deposits with or credit extended by such lender related to the loan, (ii) any tax, duty or other charge with respect to the loan (except standard income tax) or (iii) capital adequacy requirements. In addition, American’s loan agreements and other financing arrangements typically contain a withholding tax provision that requires American to pay additional amounts to the applicable lender or other financing party, generally if withholding taxes are imposed on such lender or other financing party as a result of a change in the applicable tax law.

In certain transactions, including certain aircraft financing leases and loans, the lessors, lenders and/or other parties have rights to terminate the transaction based on changes in foreign tax law, illegality or certain other events or circumstances. In such a case, American may be required to make a lump sum payment to terminate the relevant transaction.

American has general indemnity clauses in many of its airport and other real estate leases where American as lessee indemnifies the lessor (and related parties) against liabilities related to American’s use of the leased property. Generally, these indemnifications cover liabilities resulting from the negligence of the indemnified parties, but not liabilities resulting from the gross negligence or willful misconduct of the indemnified parties. In addition, American provides environmental indemnities in many of these leases for contamination related to American’s use of the leased property.

Under certain contracts with third parties, American indemnifies the third-party against legal liability arising out of an action by the third-party, or certain other parties. The terms of these contracts vary and the potential exposure under these indemnities cannot be determined. American has liability insurance protecting American for some of the obligations it has undertaken under these indemnities.

American is required to make principal and interest payments for certain special facility revenue bonds issued by municipalities primarily to build or improve airport facilities and purchase equipment, which are leased to American. The payment of principal and interest of certain special facility revenue bonds is guaranteed by American. As of December 31, 2017, the remaining lease payments through 2035 guaranteeing the principal and interest on these bonds are $589 million, which are accounted for as operating leases.

As of December 31, 2017, American had issued guarantees covering AAG’s $500 million aggregate principal amount of 6.125% senior notes due 2018, $750 million aggregate principal amount of 5.50% senior notes due 2019 and $500 million aggregate principal amount of 4.625% senior notes due 2020.

(g) Credit Card Processing Agreements

American has agreements with companies that process customer credit card transactions for the sale of air travel and other services. American’s agreements allow these processing companies, under certain conditions, to hold an amount of its cash (referred to as a holdback) equal to a portion of advance ticket sales that have been processed by that company, but for which American has not yet provided the air transportation. Additional holdback requirements in the event of material adverse changes in American’s financial condition will reduce its liquidity in the form of unrestricted cash by the amount of the holdbacks. American is not currently required to maintain any holdbacks pursuant to these requirements.

(h) Labor Negotiations

As of December 31, 2017, American employed approximately 103,100 active full-time equivalent employees. Approximately 84% of employees are covered by collective bargaining agreements with various labor unions. Negotiations for joint collective bargaining agreements covering American’s maintenance, fleet service, stock clerks, maintenance control technicians and maintenance training instructors employees are continuing. There is no assurance that a successful or timely resolution of these labor negotiations will be achieved.

(i) Other

As a result of the terrorist attacks of September 11, 2001 and the subsequent liability protections provided for by the Air Transportation Safety and System Stabilization Act (the Stabilization Act), American recorded a liability for these terrorist attacks claims equal to the related insurance receivable due to American. The Stabilization Act provides that, notwithstanding any other provision of law, liability for all claims, whether compensatory or punitive, arising from these terrorist attacks, against any air carrier shall not exceed the liability coverage maintained by the air carrier. As of December 31, 2017, claims relating to this matter have been substantially resolved and the remaining liability and the amount of the offsetting receivable are not material.