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Details of Cash From Operating Activities - Details of Items Not Involving Current Cash Flows (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Statement of Cash Flows [Abstract] |  |
Depreciation and amortization | $ 1,366 | $ 1,345
Amortization of other assets included in cost of goods sold | 215 | 257
Impairment charges [note 2] | 435 | 727
Other non-cash charges | 66 | 89
Deferred income taxes [note 10] | 17 | 7
Equity income in excess of dividends received | (10) | 0
Dividends received in excess of equity income |  | 69
Non-cash portion of Other expense, net [note 2] | (24) | (518)
Items not involving current cash flows | $ 2,065 | $ 1,976

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- Definition The aggregate amount of adjustments to net income or loss necessary to remove the effects of all items whose cash effects are investing or financing cash flows. The aggregate amount also includes all noncash expenses and income items which reduce or increase net income and are thus added back or deducted when calculating cash provided by or used in operating activities. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 + Details
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- Definition Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2420-110228 + Details
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