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Acquisitions and Dispositions (Narrative) (Details) - USD ($) $ in Thousands |  | 9 Months Ended |
--- | --- | --- | ---
Jun. 28, 2024 | Sep. 30, 2025 | Sep. 12, 2024
Educational Partners International |  |  |
Business Combination [Line Items] |  |  |
Equity method investment, ownership percentage |  |  | 68.00%
Equity method investments |  |  | $ 167,700
Valor Environmental [Member] |  |  |
Business Combination [Line Items] |  |  |
Percentage acquired | 98.00% |  |
Total purchase consideration | $ 156,400 |  |
Cash consideration | $ 156,400 |  |
Goodwill, Acquired During Period |  | $ 73,400 |
Expected tax deductible goodwill |  | 0 |
Finite-lived intangible assets |  | 92,500 |
Finite-Lived Intangible Assets, Period Increase (Decrease) |  | 43,500 |
Goodwill, Period Increase (Decrease) |  | (34,200) |
Valor Environmental [Member] | Customer Relationships |  |  |
Business Combination [Line Items] |  |  |
Finite-lived intangible assets |  | $ 82,000 |
Acquired Finite-Lived Intangible Assets, Weighted Average Useful Life |  | 17 years |
Valor Environmental [Member] | Trade Names |  |  |
Business Combination [Line Items] |  |  |
Finite-lived intangible assets |  | $ 6,000 |
Acquired Finite-Lived Intangible Assets, Weighted Average Useful Life |  | 15 years |
Valor Environmental [Member] | Other Intangible Assets |  |  |
Business Combination [Line Items] |  |  |
Finite-lived intangible assets |  | $ 4,500 |
Acquired Finite-Lived Intangible Assets, Weighted Average Useful Life |  | 5 years |
Educational Partners International |  |  |
Business Combination [Line Items] |  |  |
Goodwill, Acquired During Period |  | $ 65,300 |
Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Excluding Goodwill |  | 182,000 |
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value |  | 81,200 |
Educational Partners International | Trade Names |  |  |
Business Combination [Line Items] |  |  |
Finite-lived intangible assets |  | $ 10,000 |
Acquired Finite-Lived Intangible Assets, Weighted Average Useful Life |  | 15 years |
Educational Partners International | Technology-Based Intangible Assets |  |  |
Business Combination [Line Items] |  |  |
Finite-lived intangible assets |  | $ 2,000 |
Acquired Finite-Lived Intangible Assets, Weighted Average Useful Life |  | 5 years |
Educational Partners International | Other Intangible Assets |  |  |
Business Combination [Line Items] |  |  |
Finite-lived intangible assets |  | $ 10,000 |
Acquired Finite-Lived Intangible Assets, Weighted Average Useful Life |  | 15 years |
Educational Partners International | Other Intangible Assets |  |  |
Business Combination [Line Items] |  |  |
Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Indefinite-Lived |  | $ 160,000 |

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