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Financial Instruments - Schedule of Cash Flow Hedges Included in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023
Increase (decrease) in fair value:
Interest rate agreements	$ 24,208	$ (43,430)
Recognition of gains in earnings due to settlements:
Interest rate agreements	(14,904)	(9,965)
Total other comprehensive income (loss) from hedging, net of tax	$ 9,304	$ (53,395)	$ 149,290

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- Definition

Net of tax effect of the reclassification adjustment for accumulated gains and losses from interest rate agreements designated and qualifying as the effective portion of cash flow hedges included in accumulated comprehensive income that was realized in net income during the period.

+ References

No definition available.

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- Definition

Change in accumulated gains and losses from interest rate agreements designated and qualifying as the effective portion of cash flow hedges, net of tax effect. The after tax effect change includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

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No definition available.

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- Definition

Amount, after tax and reclassification, of gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness, attributable to parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482790/220-10-45-11

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