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Accumulated Other Comprehensive Income - Summary of Income Tax Benefit (Obligation) to Component of Other Comprehensive Income (Detail) (USD $) In Millions, unless otherwise specified | 12 Months Ended
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Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Equity [Abstract] |  |  |
Balance, beginning of year | $ (13) | $ 12 | $ (15)
Net unrealized loss (gain) | 11 | (30) | 18
Reclassification of net gain to net income | 6 | 5 | 9
Balance, end of year | 4 | (13) | 12
Balance, beginning of year | 36 | 24 | 1
Net unrealized (gain) loss | (21) | 15 | 25
Reclassification of net loss to net income | (1) | (3) | (2)
Balance, end of year | 14 | 36 | 24
Total income tax benefit | $ 18 | $ 23 | $ 36

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- Definition Accumulated Other Comprehensive Income, Income Tax Benefit Loss Netted In Accumulated Net Unrealized Gain Loss On Other Long Term Liabilities + References No definition available. + Details
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- Definition Accumulated Other Comprehensive Income, Income Tax Benefit Loss Netted In Accumulated Net Unrealized Gain Loss On Other Long Term Liabilities Reclassification Of Net Gain Loss To Net Income + References No definition available. + Details
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- Definition Accumulated Other Comprehensive Income Loss, Income Tax Netted In Accumulated Net Unrealized Gain Loss On Cash Flow Hedges Net Unrealized Gain Loss + References No definition available. + Details
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- Definition Accumulated Other Comprehensive Income Loss Income Tax Obligation Netted In Accumulated Net Unrealized Gain Loss On Cash Flow Hedges + References No definition available. + Details
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- Details
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- Definition Amount of tax expense (benefit) allocated to other comprehensive income (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 31 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 20 -Section 45 -Paragraph 11 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=18498875&loc=d3e39076-109324 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e640-108580 + Details
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