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Fair Value Disclosure (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	$ 17,819		$ 18,663
(Loss) gain on equity securities	(870)	$ 1,041
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Fair Value Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	17,819		18,663
(Loss) gain on equity securities	(600)	400
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Fair Value Measurements, Recurring \| Bellaire
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
(Loss) gain on equity securities	(300)	$ 700
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Reported Value Measurement \| Fair Value Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities cost				$ 2,000
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Reported Value Measurement \| Fair Value Measurements, Recurring \| Other Noncurrent Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	5,700		6,300
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Reported Value Measurement \| Fair Value Measurements, Recurring \| Bellaire
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities cost				$ 5,000
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Reported Value Measurement \| Fair Value Measurements, Recurring \| Bellaire \| Other Noncurrent Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	$ 12,100		$ 12,300