December 31, 2019 Gross carrying amount Accumulated amortization Intangibles, net Computer software $ 199  $ (165) $ 34  Patents and licenses 67  (65) 2  Other intangibles 693  (162) 531  Total amortizable intangible assets 959  (392) 567  Indefinite-lived trade names and trademarks 32  —  32  Total intangible assets, net $ 991  $ (392) $ 599  During the second quarter of 2019, the Company recorded a charge of $197 for intangible asset impairments associated with the Disks long-lived asset group which was recorded in Restructuring and other charges in the accompanying Statement of Consolidated Operations. See Note  O  for additional details. Computer software consists primarily of software costs associated with enterprise business solutions across Howmet's businesses. Amortization expense related to the intangible assets recorded in Provision for depreciation and amortization in the accompanying Statement of Consolidated Operations was $40, $58, and $58 for the years ended December 31, 2020, 2019, and 2018 respectively, and is expected to be in the range of approximately $37 to $43 annually from 2021 to 2025. Operating lease cost, which included short-term leases and variable lease payments and approximated cash paid, was $67, $84, and $87 in 2020, 2019, and 2018, respectively. Operating lease right-of-use assets and lease liabilities in the Consolidated Balance Sheet were as follows: Future minimum contractual operating lease obligations were as follows at December 31, 2020: December 31, 2020 2019 Right-of-use assets classified in Other noncurrent assets $ 131  $ 125  Current portion of lease liabilities classified in Other current liabilities 38  38  Long-term portion of lease liabilities classified in Other noncurrent liabilities and deferred credits 100  98  Total lease liabilities $ 138  $ 136  2021 $ 44  2022 34  2023 25  2024 17  2025 11  Thereafter 32  Total lease payments $ 163  Less: Imputed interest (25) Present value of lease liabilities $ 138  December 31, 2020 2019 Right-of-use assets obtained in exchange for operating lease obligations $ 35  $ 26  Weighted-average remaining lease term in years 6 6 Weighted-average discount rate 5.6  % 5.9  % 91 Q. Leases Table of Contents