SALE OF KANDY COMMUNICATIONS BUSINESS	12 Months Ended
SALE OF KANDY COMMUNICATIONS BUSINESS	Dec. 31, 2022
Discontinued Operations and Disposal Groups [Abstract]
SALE OF KANDY COMMUNICATIONS BUSINESS	SALE OF KANDY COMMUNICATIONS BUSINESS On August 5, 2020, the Company announced that it had entered into a definitive agreement (the "Kandy Purchase Agreement") with American Virtual Cloud Technologies, Inc. ("AVCT") to sell the Kandy Communications Business. Under the Kandy Purchase Agreement, AVCT would purchase the assets and assume certain liabilities associated with the Kandy Communications Business, as well as all of the outstanding interests in Kandy Communications LLC, a subsidiary of the Company (the "Kandy Sale"). On December 1, 2020, the Company completed the Kandy Sale. The assets acquired and liabilities assumed by AVCT in connection with the Kandy Sale were primarily comprised of accounts receivable, property and equipment, trade accounts payable and employee-related accruals. As consideration, AVCT paid Ribbon $45.0 million, subject to certain adjustments, in the form of units of AVCT’s securities (the “AVCT Units”), with each AVCT Unit consisting of: (i) $1,000 in principal amount of AVCT’s Series A-1 convertible debentures (the “Debentures”); and (ii) one warrant to purchase 100 shares of AVCT common stock, $0.0001 par value (the “Warrants”). The Company received 43,778 AVCT Units as sale consideration on the Kandy Sale Date (the "Kandy Sale Consideration"). The Debentures bore interest at a rate of 10% per annum, which was added to the principal amount of the Debenture. The entire principal amount of each Debenture, together with accrued and unpaid interest thereon, was due and payable on the earlier of the May 1, 2023 maturity date or the occurrence of a Change in Control as defined in the Kandy Purchase Agreement. Each Debenture was convertible, in whole or in part, at any time at the Company's option into that number of shares of AVCT common stock, calculated by dividing the principal amount being converted, together with all accrued and unpaid interest thereon, by the applicable conversion price, initially $3.45. The Debentures were subject to mandatory conversion if the AVCT stock price was at or above $6.00 per share for 40 trading days in any 60 consecutive trading day period, subject to the satisfaction of certain other conditions. The conversion price was subject to customary adjustments including, but not limited to, stock dividends, stock splits and reclassifications. As of February 19, 2021, the stock price had traded above $6.00 for 40 days within a 60 consecutive trading day period, and accordingly, on September 8, 2021 (the "Debenture Conversion Date"), upon the completion of customary regulatory filings by AVCT, the Debentures were converted into 13,700,421 shares of AVCT common stock (the "Debenture Shares"). The Warrants were independent of the Debentures and entitled the Company to purchase 4,377,800 shares of AVCT common stock at an exercise price of $0.01 per share. The Warrants expire on December 1, 2025, and were immediately exercisable on the Kandy Sale Date. The Company had not exercised any of the Warrants as of December 31, 2021. The Company was also subject to a lock-up provision which limited the Company's ability to sell any shares of the AVCT common stock underlying the AVCT Units prior to June 1, 2021 (the "Lock-Up Period"), except in certain transactions. The Company determined that the AVCT Units had a fair value of $84.9 million at the Kandy Sale Date, comprised of the Debentures with a fair value of $66.3 million and the Warrants with a fair value of $18.6 million. The value of the net assets sold to AVCT totaled $1.3 million, resulting in a gain on the sale of $83.6 million. The gain on the Kandy Sale is included as a component of Other (expense) income, net, in the consolidated statement of operations for the year ended December 31, 2020. The Company calculated the fair value of the Debentures using a Lattice-based valuation approach, which utilizes a binomial tree to model the different paths the price of AVCT's common stock might take over the Debentures' life by using assumptions regarding the stock price volatility and risk-free interest rate. These results were then used to calculate the fair value of the Debentures at each measurement date. The Company used the Black-Scholes valuation model for estimating the fair value of the Warrants at each measurement date. The fair value of the Warrants is affected by AVCT's stock price as well as valuation assumptions, including the volatility of AVCT's stock price, expected term of the option, risk-free interest rate and expected dividends. Both the Lattice and Black-Scholes valuation models are based on available market data, giving consideration to all of the rights and obligations of each instrument and precluding the use of "blockage" discounts or premiums in determining the fair value of a large block of financial instruments. After the expiration of the Lock-Up Period and prior to the Debenture Conversion Date, the Company valued the AVCT Units at each measurement date by multiplying the closing stock price of AVCT common stock by the number of shares upon conversion of the Debentures and Warrants. At December 31, 2021, the Company valued the Debenture Shares and Warrants (collectively, the "AVCT Investment") by multiplying the closing stock price of AVCT common stock by the number of Debenture Shares and Warrants it held. At December 31, 2021, the fair value of the AVCT Investment was $43.9 million. The Company recorded a loss of $74.8 million in the year ended December 31, 2021 arising from the change in the fair value of the AVCT Investment, and recorded a gain of $30.3 million in the year ended December 31, 2020 arising from the change in the fair value of the AVCT Units. These amounts are included as components of Other (expense) income, net, in the Company's consolidated statements of operations. The Company recorded $3.5 million of interest income in the year ended December 31, 2021, which was added to the principal amount of the Debentures prior to the Debenture Conversion Date, and which is included in Interest expense, net, in the consolidated statement of operations. The fair value of the AVCT Investment at December 31, 2021 is reported as Investments in the Company's consolidated balance sheets. The AVCT Investment is classified as a Level 1 fair value measurement at December 31, 2021 (see Note 6). The Company evaluated the nature of the AVCT Investment at December 31, 2021, and determined that it represented an equity interest on a diluted basis of approximately 15%. The Company determined that it was not the primary beneficiary of AVCT as it did not have the power to direct the activities that most significantly impact the AVCT Investment's economic performance, and therefore concluded that the Company had neither significant influence nor a controlling interest arising from the AVCT Investment that would require consolidation as of December 31, 2021. On August 29, 2022, the Company and AVCT entered into a settlement agreement which provided for, amongst other things, the cancellation of the Company's investment in the Debenture Shares and the Warrants with an aggregate fair value of $2.6 million. Pursuant to the settlement agreements, the Company and AVCT also entered into a Wind Down Agreement, pursuant to which a Reseller Agreement between the parties, as previously amended, was terminated, and the Company was granted a non-exclusive perpetual license to use and modify certain intellectual property owned by AVCT comprising WebRTC gateway technology that is integrated with Ribbon’s SBCs and Application Servers. As consideration, the Company paid AVCT $2.5 million in cash, the Debenture Shares were redeemed and canceled, and the Warrants were terminated and canceled. The perpetual license granted by AVCT is classified as Intangible assets, net in the Company's consolidated balance sheet as of December 31, 2022 in the amount of $3.9 million. The Company had no investment in AVCT as of December 31, 2022 due to the settlement agreement entered into on August 29, 2022. The Company recorded losses of $41.3 million in the year ended December 31, 2022, representing the change in the fair value of the AVCT Investment. The results of the Kandy Communications Business are excluded from the Company's consolidated results for the period subsequent to the Kandy Sale Date.