Short-Term and Long-Term Investments (Tables)

12 Months Ended

Dec. 31, 2021

Investments, Debt and Equity Securities [Abstract]

Summary of Investment

Details of our investments are as follows (in thousands):

	December 31, 2021
	Cash and Cash Equivalents		Short-Term Investments		Long-Term Investments
Measured at fair value:
Available-for-sale debt securities:
Money Market Funds	$	94,282	$	—	$	—
U.S. Treasury Obligations		—		45,215		—
Failed Auction Security		—		—		2,639
Total		94,282		45,215		2,639
Other measurement basis:
Cash on hand		88,136		—		—
Total	$	182,418	$	45,215	$	2,639

	December 31, 2020
	Cash and Cash Equivalents		Short-Term Investments		Long-Term Investments
Measured at fair value:
Available-for-sale debt securities:
Money Market Funds	$	69,493	$	—	$	—
U.S. Treasury Obligations		19,998		50,166		—
Failed Auction Security		—		—		2,517
Total		89,491		50,166		2,517
Other measurement basis:
Cash on hand		72,251		—		—
Total	$	161,742	$	50,166	$	2,517

Summary of Available-for-Sale Securities

The following is a summary of the available-for-sale securities (in thousands):

December 31, 2021	Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
U.S. Treasury Obligations	$	45,238	$	—	$	23	$	45,215
Failed Auction Security		3,000		—		361		2,639
December 31, 2020
U.S. Treasury Obligations	$	70,172	$	—	$	8	$	70,164
Failed Auction Security		3,000		—		483		2,517

Cost and Estimated Fair Value of Failed Auction Security by Contractual Maturities

The amortized cost and estimated fair value of the available-for-sale securities on December 31, 2021, by type and contractual maturities, are shown below (in thousands):

U.S. Treasury Obligations:
	Cost		Estimated Fair Value
Maturities greater than three months but less than one year	$	45,238	$	45,215
Failed Auction Security:
	Cost		Estimated Fair Value
Due in twenty to forty years	$	3,000	$	2,639