The tables below set forth, by level, our financial assets that are accounted for at fair value for the respective periods. The table does not include assets and liabilities that are measured at historical cost or any basis other than fair value (in thousands):


	Fair Value Measured at Reporting Date Using
December 31, 2020	Level 1		Level 2		Level 3		Total

Assets
Cash equivalents:
Money market funds	$	235,902	$	—	$	—	$	235,902


	$	235,902	$	—	$	—	$	235,902
Liabilities

Derivatives:
Natural gas fixed price forward contracts	$	—	$	—	$	2,574	$	2,574

Embedded EPP derivatives	—		—		5,541		5,541
Interest rate swap agreements	—		15,989		—		15,989
	$	—	$	15,989	$	8,115	$	24,104


	Fair Value Measured at Reporting Date Using
December 31, 2019	Level 1		Level 2		Level 3		Total

Assets
Cash equivalents:
Money market funds	$	276,615	$	—	$	—	$	276,615

Interest rate swap agreements	—		3		—		3
	$	276,615	$	3	$	—	$	276,618
Liabilities
Accrued expenses and other current liabilities	$	996	$	—	$	—	$	996
Derivatives:
Natural gas fixed price forward contracts	—		—		6,968		6,968

Embedded EPP derivatives	—		—		6,176		6,176
Interest rate swap agreements	—		9,241		—		9,241



	$	996	$	9,241	$	13,144	$	23,381

Tabular disclosure of the fair value measurement of assets using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes during the period attributable to the following: (1) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets) and gains or losses recognized in other comprehensive income (loss), and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (2) purchases, sales, issues, and settlements (each type disclosed separately); and (3) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs), by class of asset.

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