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Debt - Additional Information (Detail) (USD $) In Millions, unless otherwise specified | 3 Months Ended |
--- | --- | ---
Mar. 31, 2013 Agreement | Mar. 31, 2012 | Jan. 31, 2013
Debt Instrument [Line Items] |  |  |
Line of credit facility amount outstanding |  |  | $ 150
Repayment of credit facility | 150 |  |
Applicable margin on LIBOR | 1.375% |  |
Line of credit facility, expiration date | Mar. 19, 2013 |  |
Number of agreements | 3 |  |
Repayment of outstanding debt | 639 | 414 |
Aluminio [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Line of credit facility amount outstanding | 52 |  |
Repayment of outstanding debt | 52 |  |
Weighted-average interest rate | 0.72% |  |
Weighted-average maturity days | 70 |  |
First loans agreement [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Applicable margin on LIBOR | 1.25% |  |
Third loans agreement [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Repayment of credit facility | 75 |  |
Applicable margin on LIBOR | 0.95% |  |
Term loan agreement [Member] | First loans agreement [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Line of credit facility amount outstanding | 200 |  |
Applicable margin on LIBOR | 1.50% |  |
Revolving credit agreement [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Revolving credit facility, term | 5 |  |
Revolving credit agreement [Member] | First loans agreement [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Line of credit facility, expiration date | Jul. 31, 2013 |  |
Revolving credit agreement [Member] | Second loans agreement [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Line of credit facility, expiration date | Feb. 28, 2014 |  |
Agreed credit facility amount | 150 |  |
Revolving credit agreement [Member] | Third loans agreement [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Line of credit facility, expiration date | Dec. 31, 2013 |  |
Agreed credit facility amount | $ 75 |  |

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- Definition Applicable margin on London Inter Bank Offer Rate loans. + References No definition available. + Details
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Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

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- Definition Credit Facility Amount Under Agreement + References No definition available. + Details
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Balance Type: | credit
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- Definition Debt weighted average maturity days. + References No definition available. + Details
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- Definition Line Of Credit Facility, Term + References No definition available. + Details
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- Definition Number Revolving Credit Facility Agreements + References No definition available. + Details
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- Definition Weighted Average Interest Rate, Outstanding Borrowings + References No definition available. + Details
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- Details
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- Definition Amount borrowed under the credit facility as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 + Details
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- Definition Date the credit facility terminates, in CCYY-MM-DD format. + 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 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 + Details
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- Definition The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 18 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 Reference 3: 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=6943989&loc=d3e3291-108585 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 20 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Definition The cash outflow for the settlement of obligation drawn 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 Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 18 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 Reference 3: 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=6943989&loc=d3e3291-108585 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 20 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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