NOTES TO CONSOLIDATED FINANCIAL STATEMENTS - Continued Unum Group and Subsidiaries Note 4 - Derivative Financial Instruments - Continued Fair Value Hedges As of December 31, 2020 and 2019, we had $362.4 million and $249.4 million notional amount of receive fixed, pay fixed, open current and forward foreign currency interest rate swaps to hedge fixed income foreign currency-denominated securities. At December 31, 2019, we had $250.0 million notional amount of receive fixed, pay variable interest rate swaps to hedge the changes in the fair value of certain fixed rate long-term debt which matured in the third quarter of 2020 along with the hedged debt. These swaps effectively converted the associated fixed rate long-term debt into floating rate debt and provided for a better matching of interest rates with our short-term investments, which have frequent interest rate resets similar to a floating rate security. The following table summarizes the carrying amount of hedged assets and liabilities and the related cumulative basis adjustments related to our fair value hedges: Carrying Amount of Hedged Assets (Liabilities) Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of the Hedged Assets (Liabilities) December 31, 2020 December 31, 2019 December 31, 2020 December 31, 2019 (in millions of dollars) Fixed maturity securities: Receive fixed functional currency interest, pay fixed foreign currency interest $ 404.5  $ 239.4  $ 24.4  $ 1.1  Long-term Debt $ —  $ (249.2) $ —  $ 0.6  For the years ended December 31, 2020, 2019, and 2018, $(1.8) million, $2.0 million, and $2.5 million respectively, of the derivative instruments' gain (loss) was excluded from the assessment of hedge effectiveness. There were no instances wherein we discontinued fair value hedge accounting due to a hedged firm commitment no longer qualifying as a fair value hedge. As of December 31, 2020 and 2019, we held $148.2 million notional amount of receive fixed, pay fixed, foreign currency interest rate swaps. These derivatives are not designated as hedges, and as such, changes in fair value related to these derivatives are reported in earnings as a component of net realized investment gain or loss. As of December 31, 2020 and 2019, we held $11.7 million and $11.4 million, respectively, notional amount of single name credit default swaps. We entered into these swaps in order to mitigate the credit risk associated with specific securities owned. As of December 31, 2020 and 2019, we held $11.9 million and $8.9 million, respectively, notional amount of foreign currency forwards to mitigate the foreign currency risk associated with specific securities owned. We have an embedded derivative in a modified coinsurance arrangement for which we include in our realized investment gains and losses a calculation intended to estimate the value of the option of our reinsurance counterparty to cancel the reinsurance contract with us. However, neither party can unilaterally terminate the reinsurance agreement except in extreme circumstances resulting from regulatory supervision, delinquency proceedings, or other direct regulatory action. Cash settlements or collateral related to this embedded derivative are not required at any time during the reinsurance contract or at termination of the reinsurance contract. There are no credit-related counterparty triggers, and any accumulated embedded derivative gain or loss reduces to zero over time as the reinsured business winds down. Derivatives not Designated as Hedging Instruments 163