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Financial Instruments and Risk Management - Details of Securities that Currently are in Unrealized Loss Position (Detail) (USD $) In Millions, unless otherwise specified | Dec. 31, 2012
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Schedule of Available-for-sale Securities [Line Items] |
Less than 12 months, Fair Values |
Less than 12 months, Unrealized Losses |
More than 12 months, Fair Values | 88
More than 12 months, Unrealized Losses | (1)
Total, Fair Values | 88
Total, Unrealized Losses | (1)
Senior Debt Floating Rate Notes [Member] |
Schedule of Available-for-sale Securities [Line Items] |
Less than 12 months, Fair Values |
Less than 12 months, Unrealized Losses |
More than 12 months, Fair Values | 88
More than 12 months, Unrealized Losses | (1)
Total, Fair Values | 88
Total, Unrealized Losses | $ (1)

X
- Definition Amount of accumulated pre-tax unrealized loss on investments in available-for-sale securities that have been in a loss position for twelve months or longer. + References No definition available. + Details
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X
- Definition Amount of accumulated pre-tax unrealized loss on investments on securities classified as available-for-sale securities recognized in AOCI. + References No definition available. + Details
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- Definition Amount of accumulated pre-tax unrealized loss on investments in available-for-sale securities that have been in a loss position for less than twelve months impacting investments. + References No definition available. + Details
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- Definition This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
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- Definition This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
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- Definition This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for twelve months or longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
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