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Transactions - Additional Information (Detail) - USD ($) $ in Millions | 9 Months Ended |
--- | --- | ---
Sep. 30, 2020 | Dec. 31, 2019
Transactions [Line Items] |  |
Assets held-for-sale | $ 6 | $ 34
Liabilities held-for-sale | 1 | $ 6
Asset impairment charges | 320 |
Held-for-Sale [Member] |  |
Transactions [Line Items] |  |
Assets held-for-sale | 4 |
Liabilities held-for-sale | 1 |
Maximum [Member] | Held-for-Sale [Member] |  |
Transactions [Line Items] |  |
Asset impairment charges | 1 |
Impairment charges [Member] | Maximum [Member] |  |
Transactions [Line Items] |  |
Loss on sale of business | $ (1) |

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- Definition Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant. + 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 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 1B -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109239629&loc=SL4582445-111684 + Details
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