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Description of Business and Summary of Significant Accounting Policies - Additional Information (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2020 USD ($) subsidiary | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Number of owned subsidiaries | subsidiary | 2 |  |
Years forecasted in goodwill impairment income approach | 5 years |  |
Advertising expense | $ | $ 191 | $ 193 | $ 183
Valuation, Income Approach |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Fair value approach, weighted average, percentage | 75.00% |  |
Valuation, Market Approach |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Fair value approach, weighted average, percentage | 25.00% |  |

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- Definition Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 720 -SubTopic 35 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6420018&loc=d3e36677-107848 + Details
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