Financial Instruments Other Comprehensive Income (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Other Comprehensive Income [Abstract]
Interest rate agreements	$ (25,966)	$ 43,184
Interest rate agreements	3,022	1,752
Total other comprehensive income from hedging, net of tax	(22,944)	$ 44,936	$ 75,222
Interest rate agreements
Expected Earnings [Line Items]
FY2020	(4,212)
FY2021	(4,212)
FY2022	(4,212)
FY2023	(4,212)
FY2024	(4,212)
Thereafter	(93,655)
Total	$ (114,715)

Cash Flow Hedge Gain (Loss) To Be Recassiflied, Total

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- Definition

Cash Flow Hedge Gain (Loss) To Be Reclassifed Year Two

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No definition available.

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Cash Flow Hedge Gain (Loss) To Be Reclassified After Year Five

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Cash Flow Hedge Gain (Loss) To Be Reclassified Year Five

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Cash Flow Hedge Gain (Loss) To Be Reclassified Year Four

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No definition available.

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Cash Flow Hedge Gain (Loss) To Be Reclassified Year Three

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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-- None. No documentation exists for this element. --

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No definition available.

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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.

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No definition available.

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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

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669646-108580

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