Fair Value Measurements and Financial Instruments Fair value of financial instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Liabilities, fair value disclosure [Abstract]
Available-for-sale debt securities:	$ 40,610	$ 25,518
Marketable equity securities:	10,276	18,110
Revolving credit facility, noncurrent	206,262	150,433
Carrying value
Liabilities, fair value disclosure [Abstract]
Available-for-sale debt securities:	40,610	25,518
Marketable equity securities:		18,110
Revolving credit facility, noncurrent	206,262	150,433
Senior unsecured notes, noncurrent	60,000	75,000
Term loans, noncurrent	8,409	5,854
Total	274,671	231,287
Fair value
Liabilities, fair value disclosure [Abstract]
Available-for-sale debt securities:	40,610	25,518
Marketable equity securities:	10,276	18,110
Revolving credit facility, noncurrent	206,262	150,433
Senior unsecured notes, noncurrent	57,335	74,968
Term loans, noncurrent	8,420	5,610
Total	$ 272,017	$ 231,011

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Fair value portion of notes payable.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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