Note 15. Commitments and Contingencies Credit Facility In August 2018, the Company entered into a revolving credit agreement with certain lenders, which provides for a $500.0 million unsecured revolving credit facility maturing on August 7, 2023. In connection with entering into the $500.0 million credit facility, the Company also terminated its $1.0 billion unsecured revolving credit facility. The Company is obligated to pay interest on loans under the new credit facility and other customary fees for a credit facility of this size and type, including an upfront fee and an unused commitment fee. The interest rate for the new credit facility is determined based on calculations using certain market rates as set forth in the credit agreement. As of December 31, 2018, no amounts had been drawn under the credit facility. Operating and Capital Leases The Company has entered into various non-cancelable operating lease agreements for certain offices and data center facilities with contractual lease periods expiring between 2019 and 2028. During the year ended December 31, 2018 and 2017, the Company entered into several sublease agreements for office space that the Company is not fully utilizing. The Company also has lease arrangements for certain server and networking equipment that are accounted for as capital leases and included in property and equipment on the consolidated balance sheets. A summary of gross lease commitments and sublease income as of December 31, 2018 is as follows (in thousands): Operating Sublease Capital Leases Income Leases Years Ending December 31, 2019 $ 161,932 $ (24,312 ) $ 70,506 2020 151,751 (15,144 ) 23,845 2021 110,853 (11,762 ) 569 2022 89,398 (1,319 )  2023 62,137   Thereafter 263,441   $ 839,512 $ (52,537 ) 94,920 Less: Amounts representing interest 2,480 Total capital lease obligation 92,440 Less: Short-term portion 68,046 Long-term portion $ 24,394 Rent expense, net of sublease income, under the Companys operating leases, including co-location arrangements for the Companys data centers, was $138.8 million, $117.9 million and $155.7 million for the years ended December 31, 2018, 2017 and 2016, respectively. Contractual Obligations Our principal commitments consist of obligations under the Notes (including principal and coupon interest), capital and operating leases for equipment, office space and co-located data center facilities, as well as non-cancellable contractual commitments. The following table summarizes our commitments to settle contractual obligations in cash as of December 31, 2018: Payments Due by Year Total 2019 2020-2021 2022-2023 Thereafter (In thousands) 2019 Notes $ 937,338 $ 937,338 $  $  $  2021 Notes 982,646 9,540 973,106   2024 Notes 1,165,781 2,867 5,742 5,734 1,151,438 Operating lease obligations (1) 839,512 161,932 262,604 151,535 263,441 Capital lease obligations 94,920 70,506 24,414   Other contractual commitments (2) 346,922 65,768 135,205 134,404 11,545 Total contractual obligations $ 4,367,119 $ 1,247,951 $ 1,401,071 $ 291,673 $ 1,426,424 (1) The Company has entered into several sublease agreements for office space that it is not fully utilizing. Under the sublease agreements, the Company will receive approximately $52.5 million in sublease income over the next four years. (2) Other contractual commitments are non-cancelable contractual commitments primarily related to the Companys infrastructure services, bandwidth and other services arrangements. Legal Proceedings Beginning in September 2016, multiple putative class actions and derivative actions were filed in state and federal courts in the United States against Twitter, Twitters directors, and/or certain officers alleging false and misleading statements in violation of securities laws and breach of fiduciary duty. The putative class actions were consolidated in the U.S. District Court for the Northern District of California. On October 16, 2017, the court granted in part and denied in part the Companys motion to dismiss. On July 17, 2018, the court granted plaintiffs' motion for class certification in the consolidated securities action. The Company disputes the claims and intends to continue to defend the lawsuits vigorously. The Company is also currently involved in, and may in the future be involved in, legal proceedings, claims, investigations, and government inquiries arising in the ordinary course of business. These proceedings, which include both individual and class action litigation and administrative proceedings, have included, but are not limited to matters involving content on the platform, intellectual property, privacy, securities, employment and contractual rights. Legal fees and other costs associated with such actions are expensed as incurred. The Company assesses, in conjunction with its legal counsel, the need to record a liability for litigation and contingencies. Litigation accruals are recorded when and if it is determined that a loss related matter is both probable and reasonably estimable. Material loss contingencies that are reasonably possible of occurrence, if any, are subject to disclosure. As of December 31, 2018, except for the above referenced class actions and derivative actions, there was no litigation or contingency with at least a reasonable possibility of a material loss. No material losses have been recorded during the years ended December 31, 2018, 2017 and 2016 with respect to litigation or loss contingencies. Non-Income Taxes The Company is under audit by various domestic and foreign tax authorities and currently involved in a number of tax disputes related to non-income tax matters. The subject matter of non-income tax audits primarily arises from disputes on the tax treatment and tax rate applied to the sale of the Companys products and services in these jurisdictions and the tax treatment of certain employee benefits. The Company accrues non-income taxes that may result from examinations by, or any negotiated agreements with, these tax authorities when a loss is probable and reasonably estimable. If the Company determines that a loss is reasonably possible and the loss or range of loss can be estimated, it discloses the reasonably possible loss or range of loss. The Company believes these matters are without merit and it is defending itself vigorously. Due to the inherent complexity and uncertainty of these matters and judicial process in certain jurisdictions, the final outcome may be materially different from the Companys expectations. Indemnification In the ordinary course of business, the Company often includes standard indemnification provisions in its arrangements with its customers, partners, suppliers and vendors. Pursuant to these provisions, the Company may be obligated to indemnify such parties for losses or claims suffered or incurred in connection with its service, breach of representations or covenants, intellectual property infringement or other claims made against such parties. These provisions may limit the time within which an indemnification claim can be made. It is not possible to determine the maximum potential amount under these indemnification obligations due to the limited history of prior indemnification claims and the unique facts and circumstances involved in each particular agreement. The Company has never incurred significant expense defending its licensees against third-party claims, nor has it ever incurred significant expense under its standard service warranties or arrangements with its customers, partners, suppliers and vendors. Accordingly, the Company had no liabilities recorded for these provisions as of December 31, 2018 and 2017.