DEBT	12 Months Ended
Dec. 31, 2019
Debt Disclosure [Abstract]
DEBT	DEBT Assumed Senior Secured Credit Agreement On the Merger Date and in connection with the Merger, the Company assumed the GENBAND Credit Agreement with SVB, which had outstanding borrowings and letters of credit totaling $17.9 million and $2.9 million, respectively, and an average interest rate of 4.67%. GENBAND had entered into the GENBAND Credit Agreement with SVB effective July 1, 2016, with two of its operating subsidiaries as borrowers and GENBAND as the guarantor. The GENBAND Credit Agreement had a maturity date of July 1, 2019 and provided for revolving loans, including letters of credit and swingline loans, not to exceed $50 million in total, with potential further increases of $75 million available for a total revolving line of credit of up to $125 million. The GENBAND Credit Agreement was superseded by a Senior Secured Credit Facilities Credit Agreement (the "2017 Credit Facility"), which was entered into on December 21, 2017 and is discussed below. Senior Secured Credit Facility On December 21, 2017, the Company entered into the 2017 Credit Facility by and among the Company, as a guarantor, Sonus Networks, Inc., as the borrower (“Borrower”), SVB, as administrative agent (in such capacity, the “Administrative Agent”), issuing lender, swingline lender and lead arranger and the lenders party thereto (each referred to individually as a “Lender”, and collectively, the “Lenders”), which refinanced the GENBAND Credit Agreement. The 2017 Credit Facility included $100 million of commitments, the full amount of which was available for revolving loans, a $15 million sublimit that was available for letters of credit and a $15 million sublimit that was available for swingline loans. The 2017 Credit Facility contained procedures for additional financial institutions to become lenders or for any existing lender to increase its commitment under the facility, subject to an available increase of $50 million for all incremental commitments under the 2017 Credit Facility. On June 24, 2018, the Company amended the 2017 Credit Facility (the "2018 Credit Facility") to, among other things, permit the Edgewater Acquisition and related transactions. The indebtedness and other obligations under the 2018 Credit Facility were unconditionally guaranteed on a senior secured basis by the Company and each other material U.S. domestic subsidiary of the Company (collectively, the "Guarantors"). The 2018 Credit Facility was secured by first-priority liens on substantially all of the assets of the Borrower and the Guarantors, including the Company. The 2018 Credit Facility required periodic interest payments on outstanding borrowings until maturity. The Borrower could prepay all revolving loans under the 2018 Credit Facility at any time without premium or penalty (other than customary LIBOR breakage costs), subject to certain notice requirements. Revolving loans under the 2018 Credit Facility bore interest at the Borrower’s option at either the Eurodollar (LIBOR) rate plus a margin ranging from 2.50% to 3.00% per year or the base rate (the highest of the Federal Funds rate plus 0.50%, or the prime rate announced from time to time in The Wall Street Journal) plus a margin ranging from 1.50% to 2.00% per year (such margins being referred to as the “Applicable Margin”). The Applicable Margin varied depending on the Company’s consolidated leverage ratio (as defined in the 2018 Credit Facility). The base rate and the LIBOR rate were each subject to a zero percent floor. The Borrower was charged a commitment fee ranging from 0.25% to 0.40% per year on the daily amount of the unused portions of the commitments under the 2018 Credit Facility. Additionally, with respect to all letters of credit outstanding under the 2018 Credit Facility, the Borrower was charged a fronting fee of 0.125% per year and an outstanding letter of credit fee equal to the Applicable Margin for base rate loans ranging from 1.50% to 2.00% times the amount of the outstanding letters of credit. The 2018 Credit Facility required compliance with certain financial covenants, including a minimum consolidated quick ratio, minimum consolidated interest coverage ratio and maximum consolidated leverage ratio, all of which were defined in the 2018 Credit Facility and tested on a quarterly basis. In addition, the 2018 Credit Facility contained various covenants that, among other restrictions, limited the Company’s and its subsidiaries’ ability to enter into certain types of transactions, including, but not limited to: incurring or assuming indebtedness, making acquisitions or engaging in mergers, making investments, repurchasing equity and paying dividends, selling or otherwise transferring assets, changing the nature of its business and amending or making prepayments on certain junior debt. The Company was in compliance with all covenants of the 2018 Credit Facility as of December 31, 2018. The 2018 Credit Facility contained events of default that are customary for a secured credit facility. If an event of default relating to bankruptcy or other insolvency events with respect to a borrower occurred, all obligations under the 2018 Credit Facility would immediately become due and payable. If any other event of default existed under the 2018 Credit Facility, the lenders could accelerate the maturity of the obligations outstanding under the 2018 Credit Facility and exercise other rights and remedies, including charging a default rate of interest equal to 2.00% per year above the rate that would otherwise be applicable. In addition, if any event of default existed under the 2018 Credit Facility, the lenders could commence foreclosure or other actions against the collateral. If any default existed under the 2018 Credit Facility, or if the Borrower was unable to make any of the representations and warranties as stated in the 2018 Credit Facility at the applicable time, the Borrower would be unable to borrow funds or have letters of credit issued under the 2018 Credit Facility, which, depending on the circumstances prevailing at that time, could have a material adverse effect on the Borrower’s liquidity and working capital. At December 31, 2018, the Company had an outstanding debt balance of $55.0 million at a weighted average interest rate of 5.96% and $2.7 million of outstanding letters of credit at an interest rate of 1.75% under the 2018 Credit Facility. The 2018 Credit Facility was superseded by a Senior Secured Credit Facilities Credit Agreement (the "2019 Credit Facility") which was entered into on April 29, 2019 and which is discussed below. 2019 Credit Facility On April 29, 2019, the Company, as guarantor, and Ribbon Communications Operating Company, Inc., as borrower, entered into the 2019 Credit Facility, which provides for a $50 million term loan facility that was advanced in full on April 29, 2019 and a $100 million revolving line of credit. The 2019 Credit Facility also includes procedures for additional financial institutions to become syndicate lenders, or for any existing lender to increase its commitment under either the term loan facility or the revolving loan facility, subject to an aggregate increase of $75 million for incremental commitments under the 2019 Credit Facility. The 2019 Credit Facility is scheduled to mature in April 2024. At December 31, 2019, the Company had an outstanding term loan debt balance of $48.8 million at an interest rate and an outstanding revolving line of credit balance of $8.0 million with a combined average interest rate of 3.30%, and $5.4 million of outstanding letters of credit at an interest rate of 1.50%. The indebtedness and other obligations under the 2019 Credit Facility are unconditionally guaranteed on a senior secured basis by the Company and each other material U.S. domestic subsidiary of the Company (collectively, the “Guarantors”). The 2019 Credit Facility is secured by first-priority liens on substantially all of the assets of the Borrower and the Guarantors, including the Company. The 2019 Credit Facility requires periodic interest payments on any outstanding borrowings under the facility. The Borrower may prepay all revolving loans under the 2019 Credit Facility at any time without premium or penalty (other than customary LIBOR breakage costs), subject to certain notice requirements. Revolving loans under the 2019 Credit Facility bear interest at the Borrower’s option at either the Eurodollar (LIBOR) rate plus a margin ranging from 1.50% to 3.00% per year or the base rate (the highest of the Federal Funds rate plus 0.50%, or the prime rate announced from time to time in The Wall Street Journal) plus a margin ranging from 0.50% to 2.00% per year (such margins being referred to as the “Applicable Margin”). The Applicable Margin varies depending on the Company’s consolidated leverage ratio (as defined in the 2019 Credit Facility). The base rate and the LIBOR rate are each subject to a zero percent floor. The 2019 Credit Facility requires compliance with certain financial covenants, including a minimum consolidated quick ratio, minimum consolidated fixed charge coverage ratio and maximum consolidated leverage ratio, all of which are defined in the 2019 Credit Facility and tested on a quarterly basis. The Company was in compliance with all covenants of the 2019 Credit Facility at December 31, 2019. In addition, the 2019 Credit Facility contains various covenants that, among other restrictions, limit the Company’s and its subsidiaries’ ability to enter into certain types of transactions, including, but not limited to: incurring or assuming indebtedness; granting or assuming liens; making acquisitions or engaging in mergers; making dividend and certain other restricted payments; making investments; selling or otherwise transferring assets; engaging in transactions with affiliates; entering into sale and leaseback transactions; entering into burdensome agreements; changing the nature of its business; modifying its organizational documents; and amending or making prepayments on certain junior debt. The 2019 Credit Facility contains events of default that are customary for a secured credit facility. If an event of default relating to bankruptcy or other insolvency events with respect to a borrower occurs, all obligations under the 2019 Credit Facility will immediately become due and payable. If any other event of default exists under the 2019 Credit Facility, the lenders may accelerate the maturity of the obligations outstanding under the 2019 Credit Facility and exercise other rights and remedies, including charging a default rate of interest equal to 2.00% per year above the rate that would otherwise be applicable. In addition, if any event of default exists under the 2019 Credit Facility, the lenders may commence foreclosure or other actions against the collateral. If any default exists under the 2019 Credit Facility, or if the Borrower is unable to make any of the representations and warranties as stated in the 2019 Credit Facility at the applicable time, the Borrower will be unable to borrow funds or have letters of credit issued under the 2019 Credit Facility, which, depending on the circumstances prevailing at that time, could have a material adverse effect on the Borrower’s liquidity and working capital. Promissory Note In connection with the Merger, on October 27, 2017, the Company issued a promissory note for $22.5 million to certain of GENBAND's equityholders (the "Promissory Note"). The Promissory Note did not amortize and the principal thereon was payable in full on the third anniversary of its execution. Interest on the Promissory Note was payable quarterly in arrears and accrued at a rate of 7.5% per year for the first six months after issuance, and thereafter at a rate of 10% per year. The failure to make any payment under the Promissory Note when due and, with respect to payment of any interest, the continuation of such failure for a period of thirty days thereafter, constituted an event of default under the Promissory Note. If an event of default occurred under the Promissory Note, the payees could declare the entire balance of the Promissory Note due and payable (including principal and accrued and unpaid interest) within five business days of the payees' notification to the Company of such acceleration. Interest that was not paid on the interest payment date would increase the principal amount of the Promissory Note. At December 31, 2018, the Promissory Note balance was $24.1 million, comprised of $22.5 million of principal, plus $1.6 million of interest converted to principal. On April 29, 2019, concurrently with the closing of the 2019 Credit Facility as discussed above, the Company repaid in full all outstanding amounts under the Promissory Note, aggregating $24.7 million. The Company did not incur any early termination penalties in connection with this repayment.

DEBT

Assumed Senior Secured Credit Agreement

On the Merger Date and in connection with the Merger, the Company assumed the GENBAND Credit Agreement with SVB, which had outstanding borrowings and letters of credit totaling $17.9 million and $2.9 million, respectively, and an average interest rate of 4.67%. GENBAND had entered into the GENBAND Credit Agreement with SVB effective July 1, 2016, with two of its operating subsidiaries as borrowers and GENBAND as the guarantor. The GENBAND Credit Agreement had a maturity date of July 1, 2019 and provided for revolving loans, including letters of credit and swingline loans, not to exceed $50 million in total, with potential further increases of $75 million available for a total revolving line of credit of up to $125 million. The GENBAND Credit Agreement was superseded by a Senior Secured Credit Facilities Credit Agreement (the "2017 Credit Facility"), which was entered into on December 21, 2017 and is discussed below.

Senior Secured Credit Facility

On December 21, 2017, the Company entered into the 2017 Credit Facility by and among the Company, as a guarantor, Sonus Networks, Inc., as the borrower (“Borrower”), SVB, as administrative agent (in such capacity, the “Administrative Agent”), issuing lender, swingline lender and lead arranger and the lenders party thereto (each referred to individually as a “Lender”, and collectively, the “Lenders”), which refinanced the GENBAND Credit Agreement. The 2017 Credit Facility included $100 million of commitments, the full amount of which was available for revolving loans, a $15 million sublimit that was available for letters of credit and a $15 million sublimit that was available for swingline loans. The 2017 Credit Facility contained procedures for additional financial institutions to become lenders or for any existing lender to increase its commitment under the facility, subject to an available increase of $50 million for all incremental commitments under the 2017 Credit Facility. On June 24, 2018, the Company amended the 2017 Credit Facility (the "2018 Credit Facility") to, among other things, permit the Edgewater Acquisition and related transactions.

The indebtedness and other obligations under the 2018 Credit Facility were unconditionally guaranteed on a senior secured basis by the Company and each other material U.S. domestic subsidiary of the Company (collectively, the "Guarantors"). The 2018 Credit Facility was secured by first-priority liens on substantially all of the assets of the Borrower and the Guarantors, including the Company.

The 2018 Credit Facility required periodic interest payments on outstanding borrowings until maturity. The Borrower could prepay all revolving loans under the 2018 Credit Facility at any time without premium or penalty (other than customary LIBOR breakage costs), subject to certain notice requirements.

Revolving loans under the 2018 Credit Facility bore interest at the Borrower’s option at either the Eurodollar (LIBOR) rate plus a margin ranging from 2.50% to 3.00% per year or the base rate (the highest of the Federal Funds rate plus 0.50%, or the prime rate announced from time to time in The Wall Street Journal) plus a margin ranging from 1.50% to 2.00% per year (such margins being referred to as the “Applicable Margin”). The Applicable Margin varied depending on the Company’s consolidated leverage ratio (as defined in the 2018 Credit Facility). The base rate and the LIBOR rate were each subject to a zero percent floor.

The Borrower was charged a commitment fee ranging from 0.25% to 0.40% per year on the daily amount of the unused portions of the commitments under the 2018 Credit Facility. Additionally, with respect to all letters of credit outstanding under the 2018 Credit Facility, the Borrower was charged a fronting fee of 0.125% per year and an outstanding letter of credit fee equal to the Applicable Margin for base rate loans ranging from 1.50% to 2.00% times the amount of the outstanding letters of credit.

The 2018 Credit Facility required compliance with certain financial covenants, including a minimum consolidated quick ratio, minimum consolidated interest coverage ratio and maximum consolidated leverage ratio, all of which were defined in the 2018 Credit Facility and tested on a quarterly basis. In addition, the 2018 Credit Facility contained various covenants that, among other restrictions, limited the Company’s and its subsidiaries’ ability to enter into certain types of transactions, including, but not limited to: incurring or assuming indebtedness, making acquisitions or engaging in mergers, making investments, repurchasing equity and paying dividends, selling or otherwise transferring assets, changing the nature of its business and amending or making prepayments on certain junior debt. The Company was in compliance with all covenants of the 2018 Credit Facility as of December 31, 2018.

The 2018 Credit Facility contained events of default that are customary for a secured credit facility. If an event of default relating to bankruptcy or other insolvency events with respect to a borrower occurred, all obligations under the 2018 Credit Facility would immediately become due and payable. If any other event of default existed under the 2018 Credit Facility, the lenders could accelerate the maturity of the obligations outstanding under the 2018 Credit Facility and exercise other rights and remedies, including charging a default rate of interest equal to 2.00% per year above the rate that would otherwise be applicable. In addition, if any event of default existed under the 2018 Credit Facility, the lenders could commence foreclosure or other actions against the collateral.

If any default existed under the 2018 Credit Facility, or if the Borrower was unable to make any of the representations and warranties as stated in the 2018 Credit Facility at the applicable time, the Borrower would be unable to borrow funds or have letters of credit issued under the 2018 Credit Facility, which, depending on the circumstances prevailing at that time, could have a material adverse effect on the Borrower’s liquidity and working capital.

At December 31, 2018, the Company had an outstanding debt balance of $55.0 million at a weighted average interest rate of 5.96% and $2.7 million of outstanding letters of credit at an interest rate of 1.75% under the 2018 Credit Facility. The 2018 Credit Facility was superseded by a Senior Secured Credit Facilities Credit Agreement (the "2019 Credit Facility") which was entered into on April 29, 2019 and which is discussed below.

2019 Credit Facility

On April 29, 2019, the Company, as guarantor, and Ribbon Communications Operating Company, Inc., as borrower, entered into the 2019 Credit Facility, which provides for a $50 million term loan facility that was advanced in full on April 29, 2019 and a $100 million revolving line of credit. The 2019 Credit Facility also includes procedures for additional financial institutions to become syndicate lenders, or for any existing lender to increase its commitment under either the term loan facility or the revolving loan facility, subject to an aggregate increase of $75 million for incremental commitments under the 2019 Credit Facility. The 2019 Credit Facility is scheduled to mature in April 2024. At December 31, 2019, the Company had an outstanding term loan debt balance of $48.8 million at an interest rate and an outstanding revolving line of credit balance of $8.0 million with a combined average interest rate of 3.30%, and $5.4 million of outstanding letters of credit at an interest rate of 1.50%.

The indebtedness and other obligations under the 2019 Credit Facility are unconditionally guaranteed on a senior secured basis by the Company and each other material U.S. domestic subsidiary of the Company (collectively, the “Guarantors”). The 2019 Credit Facility is secured by first-priority liens on substantially all of the assets of the Borrower and the Guarantors, including the Company.

The 2019 Credit Facility requires periodic interest payments on any outstanding borrowings under the facility. The Borrower may prepay all revolving loans under the 2019 Credit Facility at any time without premium or penalty (other than customary LIBOR breakage costs), subject to certain notice requirements.

Revolving loans under the 2019 Credit Facility bear interest at the Borrower’s option at either the Eurodollar (LIBOR) rate plus a margin ranging from 1.50% to 3.00% per year or the base rate (the highest of the Federal Funds rate plus 0.50%, or the prime rate announced from time to time in The Wall Street Journal) plus a margin ranging from 0.50% to 2.00% per year (such margins being referred to as the “Applicable Margin”). The Applicable Margin varies depending on the Company’s consolidated leverage ratio (as defined in the 2019 Credit Facility). The base rate and the LIBOR rate are each subject to a zero percent floor.

The 2019 Credit Facility requires compliance with certain financial covenants, including a minimum consolidated quick ratio, minimum consolidated fixed charge coverage ratio and maximum consolidated leverage ratio, all of which are defined in the 2019 Credit Facility and tested on a quarterly basis. The Company was in compliance with all covenants of the 2019 Credit Facility at December 31, 2019.

In addition, the 2019 Credit Facility contains various covenants that, among other restrictions, limit the Company’s and its subsidiaries’ ability to enter into certain types of transactions, including, but not limited to: incurring or assuming indebtedness; granting or assuming liens; making acquisitions or engaging in mergers; making dividend and certain other restricted payments; making investments; selling or otherwise transferring assets; engaging in transactions with affiliates; entering into sale and leaseback transactions; entering into burdensome agreements; changing the nature of its business; modifying its organizational documents; and amending or making prepayments on certain junior debt.

The 2019 Credit Facility contains events of default that are customary for a secured credit facility. If an event of default relating to bankruptcy or other insolvency events with respect to a borrower occurs, all obligations under the 2019 Credit Facility will immediately become due and payable. If any other event of default exists under the 2019 Credit Facility, the lenders may accelerate the maturity of the obligations outstanding under the 2019 Credit Facility and exercise other rights and remedies, including charging a default rate of interest equal to 2.00% per year above the rate that would otherwise be applicable. In addition, if any event of default exists under the 2019 Credit Facility, the lenders may commence foreclosure or other actions against the collateral.

If any default exists under the 2019 Credit Facility, or if the Borrower is unable to make any of the representations and warranties as stated in the 2019 Credit Facility at the applicable time, the Borrower will be unable to borrow funds or have letters of credit issued under the 2019 Credit Facility, which, depending on the circumstances prevailing at that time, could have a material adverse effect on the Borrower’s liquidity and working capital.

Promissory Note

In connection with the Merger, on October 27, 2017, the Company issued a promissory note for $22.5 million to certain of GENBAND's equityholders (the "Promissory Note"). The Promissory Note did not amortize and the principal thereon was payable in full on the third anniversary of its execution. Interest on the Promissory Note was payable quarterly in arrears and accrued at a rate of 7.5% per year for the first six months after issuance, and thereafter at a rate of 10% per year. The failure to make any payment under the Promissory Note when due and, with respect to payment of any interest, the continuation of such failure for a period of thirty days thereafter, constituted an event of default under the Promissory Note. If an event of default occurred under the Promissory Note, the payees could declare the entire balance of the Promissory Note due and payable (including principal and accrued and unpaid interest) within five business days of the payees' notification to the Company of such acceleration. Interest that was not paid on the interest payment date would increase the principal amount of the Promissory Note. At December 31, 2018, the Promissory Note balance was $24.1 million, comprised of $22.5 million of principal, plus $1.6 million of interest converted to principal.

On April 29, 2019, concurrently with the closing of the 2019 Credit Facility as discussed above, the Company repaid in full all outstanding amounts under the Promissory Note, aggregating $24.7 million. The Company did not incur any early termination penalties in connection with this repayment.