Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021	Jun. 30, 2021	Dec. 31, 2020
Cash And Cash Equivalents
Money Market Funds	$ 6,979	$ 29,876
Commercial Paper	7,841	0
Cash Deposits	1,617	2,388
Total Cash And Cash Equivalents	16,437	32,264	$ 17,070	$ 22,450
Short-term Investments
Commercial Paper (held-to-maturity)	20,495	2,248
Bonds (held-to-maturity)	13,418	26,831
Equity Securities (available For Sale)	243	0
Allowance For Credit Losses	(10)	(20)
Total Short-term Investments	34,146	29,059
Long-term Investments
Bonds (held-to-maturity)	10,586	13,405
Equity Securities (available For Sale)	4,828	5,468
Mutual Funds (available For Sale)	385	559
Allowance For Credit Losses	(5)	(9)
Total Long-term Investments	15,794	19,423
Total Cash, Cash Equivalents And Short And Long-term Investments	$ 66,377	$ 80,746

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Equity securities categorized neither as held-to-maturity nor trading which are intended be sold more than one year from the balance sheet date or operating cycle, if longer.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

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Amount, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity), classified as current.

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The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

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Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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