Summary of Significant Accounting Policies - Supplemental Executive Savings Plan (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	9 Months Ended
Jan. 31, 2025	Jan. 31, 2024	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Accounting Policies [Abstract]
SESP contribution amount	$ 26	$ 22
Gain (loss) on marketable securities and long-term restricted investments			$ 254	$ 192	$ 452	$ 526
Interest and dividend income			6	$ 5	19	$ 17
Short-term restricted investments (SESP)			2,808		2,808		$ 0
Long-term restricted investments (SESP)			1,481		1,481		3,797
Short-term deferred compensation (SESP)			2,808		2,808		0
Long-term deferred compensation (SESP)			$ 1,481		$ 1,481		$ 3,823

Gain (Loss) On Marketable Securities And Long-term Restricted Investments

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- Definition

Supplemental Executive Savings Plan, Contribution Amount

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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable beyond one year (or the operating cycle, if longer).

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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable within one year (or the operating cycle, if longer). Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

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Amount, after discount, accretion and premium amortization, of interest income and dividend income classified as other.

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This element represents the current portion of investments which are not defined as or included in marketable (debt, equity, or other) securities that are pledged or subject to withdrawal restrictions.

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This element represents the noncurrent portion of investments which are not defined as or included in marketable (debt, equity, or other) securities that are pledged or subject to withdrawal restrictions.

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