Face (par) amount of debt instrument at time of issuance.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Amount, after accumulated amortization, of debt discount.

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-Publisher FASB
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-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
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- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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- Definition

Debt instrument maturity year.

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Debt - Long-term Debt (Parenthetical) (Detail) € in Millions	6 Months Ended
	Mar. 31, 2017 USD ($)	Sep. 30, 2016 USD ($)	Mar. 31, 2017 EUR (€)	Sep. 30, 2016 EUR (€)	Mar. 31, 2016
Debt Instrument [Line Items]
Face or principal amount of debt instrument	$ 2,808,000,000	$ 2,815,000,000
Unamortized discount	7,000,000	3,000,000
Unamortized deferred financing costs	34,000,000	34,000,000
Revolving Credit Facility
Debt Instrument [Line Items]
Commitments under revolving credit facility	150,000,000	150,000,000
Letters of credit outstanding	12,000,000	5,000,000
Revolving Credit Facility Outstanding	$ 0	$ 0
6.00% Senior Secured Notes due 2021
Debt Instrument [Line Items]
Interest rate	6.00%		6.00%		6.00%
6.00% Senior Secured Notes due 2021 \| Acquisition Corp.
Debt Instrument [Line Items]
Interest rate	6.00%	6.00%	6.00%	6.00%
Due date of Senior Secured Notes	2021	2021
Face or principal amount of debt instrument		$ 450,000,000
Unamortized deferred financing costs		$ 6,000,000
6.25% Senior Secured Notes due 2021
Debt Instrument [Line Items]
Interest rate	6.25%		6.25%		6.25%
6.25% Senior Secured Notes due 2021 \| Acquisition Corp.
Debt Instrument [Line Items]
Interest rate	6.25%	6.25%	6.25%	6.25%
Due date of Senior Secured Notes	2021	2021
Face or principal amount of debt instrument		$ 177,000,000		€ 158
Unamortized deferred financing costs		$ 3,000,000
5.625% Senior Secured Notes due 2022
Debt Instrument [Line Items]
Interest rate	5.625%		5.625%		5.625%
5.625% Senior Secured Notes due 2022 \| Acquisition Corp.
Debt Instrument [Line Items]
Interest rate	5.625%	5.625%	5.625%	5.625%
Due date of Senior Secured Notes	2022	2022
Face or principal amount of debt instrument	$ 248,000,000	$ 275,000,000
Unamortized deferred financing costs	$ 2,000,000	$ 3,000,000
5.00% Senior Secured Notes due 2023 \| Acquisition Corp.
Debt Instrument [Line Items]
Interest rate	5.00%	5.00%	5.00%	5.00%
Due date of Senior Secured Notes	2023	2023
Face or principal amount of debt instrument	$ 300,000,000	$ 300,000,000
Unamortized deferred financing costs	$ 4,000,000	$ 4,000,000
4.125% Senior Secured Notes due 2024
Debt Instrument [Line Items]
Interest rate	4.125%		4.125%		4.125%
4.125% Senior Secured Notes due 2024 \| Acquisition Corp.
Debt Instrument [Line Items]
Interest rate	4.125%	4.125%	4.125%	4.125%
Due date of Senior Secured Notes	2024	2024
4.875% Senior Secured Notes due 2024
Debt Instrument [Line Items]
Interest rate	4.875%		4.875%		4.875%
4.875% Senior Secured Notes due 2024 \| Acquisition Corp.
Debt Instrument [Line Items]
Interest rate	4.875%	4.875%	4.875%	4.875%
Due date of Senior Secured Notes	2024	2024
6.75% Senior Notes due 2022
Debt Instrument [Line Items]
Interest rate					6.75%
6.75% Senior Notes due 2022 \| Acquisition Corp.
Debt Instrument [Line Items]
Interest rate	6.75%	6.75%	6.75%	6.75%
Due date of Senior Secured Notes	2022	2022
Senior Term Loan Facility due 2023 \| Acquisition Corp.
Debt Instrument [Line Items]
Face or principal amount of debt instrument	$ 1,006,000,000	$ 978,000,000
Unamortized discount	7,000,000	3,000,000
Unamortized deferred financing costs	12,000,000	12,000,000
4.125% Senior Secured Notes due 2024 \| Acquisition Corp.
Debt Instrument [Line Items]
Face or principal amount of debt instrument	369,000,000		€ 345
Unamortized deferred financing costs	6,000,000
4.875% Senior Secured Notes due 2024 \| Acquisition Corp.
Debt Instrument [Line Items]
Face or principal amount of debt instrument	250,000,000
Unamortized deferred financing costs	4,000,000
6.75% Senior Notes due 2022 \| Acquisition Corp.
Debt Instrument [Line Items]
Face or principal amount of debt instrument	635,000,000	635,000,000
Unamortized deferred financing costs	$ 6,000,000	$ 6,000,000