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Shareholders' Equity - Changes in AOCI Attributable to Stockholders (Detail) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
OCI before reclassifications | $ 338 | $ (115) | $ (321) |
Amounts reclassified from AOCI | (20) | 24 | 172 |
OCI Balance | 318 | (91) | (149) |
Cumulative tax impact | (1) | 2 | (4) |
OCI Balance, net of tax | 317 | (89) | (153) |
Balance | 647 | 329 | 420 | $ 569
Cumulative tax impact | 41 | 42 | 40 | 44
Balance, net of tax | 688 | 371 | 460 | 613
Foreign Currency Translation Adjustments ("CTA") [Member] |  |  |  |
OCI before reclassifications | 224 | (57) | (202) |
Amounts reclassified from AOCI |  |  | (10) |
OCI Balance | 224 | (57) | (212) |
OCI Balance, net of tax | 224 | (57) | (212) |
Balance | 768 | 544 | 601 | 813
Balance, net of tax | 768 | 544 | 601 | 813
Accumulated Defined Benefit Plan Items [Member] |  |  |  |
OCI before reclassifications | (6) | (25) | (2) |
Amounts reclassified from AOCI | 10 | 15 | 12 |
OCI Balance | 4 | (10) | 10 |
Cumulative tax impact | (1) | 2 | (4) |
OCI Balance, net of tax | 3 | (8) | 6 |
Balance | (166) | (170) | (160) | (170)
Cumulative tax impact | 41 | 42 | 40 | 44
Balance, net of tax | (125) | (128) | (120) | (126)
Accumulated Net Gains (Losses) on Available-for-Sale Securities [Member] |  |  |  |
OCI before reclassifications | (2) |  |  |
OCI Balance | (2) |  |  |
OCI Balance, net of tax | (2) |  |  |
Balance |  | 2 | 2 | 2
Balance, net of tax |  | 2 | 2 | 2
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member] |  |  |  |
OCI before reclassifications | 122 | (33) | (117) |
Amounts reclassified from AOCI | (30) | 9 | 170 |
OCI Balance | 92 | (24) | 53 |
OCI Balance, net of tax | 92 | (24) | 53 |
Balance | 45 | (47) | (23) | (76)
Balance, net of tax | $ 45 | $ (47) | $ (23) | $ (76)

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- Definition Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e637-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e681-108580 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669686-108580 + Details
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- Definition Amount before tax of increase (decrease) in accumulated equity from transactions and other events and circumstances from non-owner sources, attributable to parent. Excludes net income (loss), and accumulated changes in equity from transactions resulting from investments by owners (distributions to owners). + References No definition available. + Details
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