Fair Value Measurements

6 Months Ended

Jun. 30, 2021

Fair Value, Measurement Inputs, Disclosure

Fair Value Measurements

The Company utilizes the market approach to measure the fair value of its financial assets. The market approach uses prices and other relevant information generated by market transactions involving identical or comparable assets. The assets classified as Level 2 primarily utilize quoted market prices or alternative pricing sources including transactions involving identical or comparable assets and models utilizing market observable inputs for valuation of these securities. No changes in valuation techniques or inputs occurred during the six months ended June 30, 2021.

Financial instruments measured at fair value on a recurring basis:


	June 30, 2021						December 31, 2020
(in thousands)	Total		Level 1		Level 2		Total		Level 1		Level 2
Cash equivalents
Money market funds	$	157,320	$	157,320	$	—	$	5,340	$	5,340	$	—
Municipal debt securities	78,996		—		78,996		34,338		—		34,338
Commercial Paper	66,292		—		66,292		48,908		—		48,908

Federal agency debt securities	—		—		—		51,400		—		51,400

Total cash equivalents	302,608		157,320		145,288		139,986		5,340		134,646
Short-term
Commercial paper	345,809		—		345,809		229,821		—		229,821

Corporate debt securities	217,631		—		217,631		166,768		—		166,768
Municipal debt securities	178,870		—		178,870		87,290		—		87,290
Federal agency debt securities	25,100		—		25,100		48,598		—		48,598
Total short-term	767,410		—		767,410		532,477		—		532,477







Total financial instruments	$	1,070,018	$	157,320	$	912,698	$	672,463	$	5,340	$	667,123

None of the Company's debt is publicly held and as a result, the Company has determined the estimated fair value of these notes to be Level 3. Certain inputs used to determine fair value are unobservable and, therefore, could be sensitive to changes in inputs. The Company utilizes the discounted cash flow method to estimate the fair value of Level 3 debt.

Carrying value and estimated fair value of long-term debt, including current maturities and without reduction for related costs, are as follows:


	June 30, 2021				December 31, 2020
(in thousands)	Carrying Value		Estimated Fair Value		Carrying Value		Estimated Fair Value		Hierarchy Level
Non-publicly held debt	$	1,366,042	$	1,170,576	$	1,555,637	$	1,191,008	3

Due to their short-term nature, the carrying amounts of cash, cash equivalents, restricted cash, accounts receivable and accounts payable approximate fair value.