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Summary of Significant Accounting Policies - Narrative (Details) $ in Millions |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Apr. 01, 2020 company | Jun. 30, 2019 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) segment | Dec. 31, 2019
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Number of independent, publicly-traded companies resulting from proposed separation transaction | company | 2 |  |  |  |
Number of reportable segments | segment |  |  |  | 4 |
Minimum percentage of estimated fair value of reporting unit to be less than carrying amount of goodwill |  |  | 50.00% |  |
Period required for impairment testing of reporting units |  |  | 3 years |  |
Impairment of goodwill |  | $ 0 | $ 4 | $ 2 |
Advance payment |  |  | $ 85 | $ 46 |
Businesses expected to be disposed within, years |  |  | 1 year |  |
Aerospace | Revenue Benchmark | Customer Concentration Risk |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Concentration risk, percentage |  |  | 60.00% | 69.00% | 71.00%

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- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 42 -URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e9054-108599 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=123594938&loc=d3e13531-108611 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123594938&loc=d3e13537-108611 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592 + Details
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