Applicable margin on LIBOR loans.

No definition available.

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- Definition

Debt covenants net leverage ratio.

+ References

No definition available.

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- Definition

Debt covenants net leverage ratio after year three.

+ References

No definition available.

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- Definition

Debt Weighted Average Maturity Term

+ References

No definition available.

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- Definition

Extended additional maturity period.

+ References

No definition available.

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- Definition

Line of credit facility, term.

+ References

No definition available.

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- Definition

Weighted average interest rate, outstanding borrowings.

+ References

No definition available.

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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

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
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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- Definition

The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585

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- Definition

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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Debt (Credit Facilities) (Detail) - USD ($)		12 Months Ended
Debt (Credit Facilities) (Detail) - USD ($)	Jul. 25, 2014	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Sep. 30, 2016
Debt Instrument [Line Items]
Ratio of indebtedness to consolidated EBITDA		4.50%
Ratio of indebtedness to consolidated EBITDA, after December 31, 2019		3.50%
Extension of maturity period		1 year
Maximum borrowing capacity		$ 715,000,000
Arconic
Debt Instrument [Line Items]
Line of credit facility, repayment		$ 810,000,000	$ 1,950,000,000	$ 1,890,000,000
Weighted-average interest rate		2.60%	1.90%	1.60%
Weighted-average maturity days		46 days	49 days	69 days
Maximum
Debt Instrument [Line Items]
Applicable margin on LIBOR loans		1.70%
Minimum
Debt Instrument [Line Items]
Applicable margin on LIBOR loans		0.70%
Revolving Credit Agreement
Debt Instrument [Line Items]
Revolving credit facility, term	5 years
Revolving Credit Agreement \| Prior to Amendment
Debt Instrument [Line Items]
Line of credit facility, outstanding borrowings	$ 4,000,000,000
Revolving Credit Agreement \| After Amendment
Debt Instrument [Line Items]
Line of credit facility, outstanding borrowings					$ 3,000,000,000
Commercial Paper \| Maximum
Debt Instrument [Line Items]
Fees paid to maintain credit facility		0.30%
Senior Unsecured Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility, outstanding borrowings		$ 0	$ 0
Amounts borrowed under the credit agreement		0	$ 0	$ 0
Expected Maturity Date Year 2017
Debt Instrument [Line Items]
Maximum borrowing capacity		640,000,000
Expected Maturity Date Year 2018
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 75,000,000