Derivative Instruments - Interest-Rate Derivatives (Details) - USD ($) $ in Millions	2 Months Ended
Sep. 30, 2019	Oct. 11, 2019
Interest Rate Swap, 6.782%
Derivative [Line Items]
Notional Principal Amount	$ 125
Weighted-Average Interest Rate	6.782%
Interest Rate Swap, 6.782% \| Subsequent Event
Derivative [Line Items]
Notional Principal Amount		$ 125
Interest Rate Swap, 6.418%
Derivative [Line Items]
Notional Principal Amount	$ 550
Weighted-Average Interest Rate	6.418%
Interest Rate Swap, 6.835%
Derivative [Line Items]
Notional Principal Amount	$ 125
Weighted-Average Interest Rate	6.835%
Interest Rate Swap, 6.891%
Derivative [Line Items]
Notional Principal Amount	$ 100
Weighted-Average Interest Rate	6.891%
Interest Rate Swap, 6.570%
Derivative [Line Items]
Notional Principal Amount	$ 250
Weighted-Average Interest Rate	6.57%
Interest Rate Swap, 6.445%
Derivative [Line Items]
Notional Principal Amount	$ 450
Weighted-Average Interest Rate	6.445%
Interest Rate Swap, 2.662%
Derivative [Line Items]
Notional Principal Amount	$ 375
Weighted-Average Interest Rate	2.662%
Interest Rate Swap, 2.802%
Derivative [Line Items]
Notional Principal Amount	$ 375
Weighted-Average Interest Rate	2.802%
Interest Rate Swap, 2.885%
Derivative [Line Items]
Notional Principal Amount	$ 375
Weighted-Average Interest Rate	2.885%
Interest Rate Swaps
Derivative [Line Items]
Net cash payments related to settlements and amendments	$ 43

Average fixed interest rate related to the group of interest rate derivatives.

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- Definition

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.

+ References

No definition available.

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

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- Definition

The cash outflow for derivative instruments during the period, which are classified as financing activities, excluding those designated as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3505-108585

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