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Fair Value Disclosure (Narrative) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023 | Dec. 31, 2023 | Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Gain (loss) on equity securities | $ 442 | $ (551) | $ 1,219 | $ 498 |  |
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 | 17,987 |  | 17,987 |  | $ 17,208 |
Gain (loss) on equity securities | (100) | (200) | (300) | (200) |  |
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] |  |  |  |  |  |
Gain (loss) on equity securities | 600 | $ (400) | 1,500 | $ 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 |  | 5,700 |  | 6,000 |
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 | $ 12,300 |  | $ 12,300 |  | $ 11,200 |

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