Income Taxes - Reconciliation of the Change in Unrecognized Tax Benefits (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
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| Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] | |||
| Balance, January 1 | $ 1,068 | $ 3,068 | $ 3,677 |
| Increases related to positions taken during the current year | 36 | 75 | 98 |
| Increases related to positions taken during prior years | 187 | 519 | 254 |
| Decreases related to positions taken during prior years | (177) | (973) | (508) |
| Settlements | (1) | (1,594) | (448) |
| Expiration of statute of limitations | (18) | (27) | (5) |
| Balance, December 31 | 1,095 | 1,068 | 3,068 |
| Changes in prior period UTBs, including interest | $ (85) | $ (741) | $ (255) |
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- Definition Effective Income Tax Rate Reconciliation, Changes in Prior Period Unrealized Tax Benefits, Including Interest, Amount No definition available.
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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