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ACQUISITIONS - AK Steel Intangible Assets and Liabilities (Details) - AK Steel $ in Millions | 3 Months Ended
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Mar. 31, 2021 USD ($)
Acquired Finite-Lived Intangible Assets [Line Items] |
Total identifiable intangible assets | $ 148
Weighted Average Life (In Years) | 17 years
Above-market supply contracts | $ (71)
Above-market supply contract, Weighted Average Useful Life (in years) | 12 years
Customer relationships |
Acquired Finite-Lived Intangible Assets [Line Items] |
Total identifiable intangible assets | $ 77
Weighted Average Life (In Years) | 18 years
Developed technology |
Acquired Finite-Lived Intangible Assets [Line Items] |
Total identifiable intangible assets | $ 60
Weighted Average Life (In Years) | 17 years
Trade names and trademarks |
Acquired Finite-Lived Intangible Assets [Line Items] |
Total identifiable intangible assets | $ 11
Weighted Average Life (In Years) | 10 years

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- Definition Weighted average amortization period of finite-lived intangible liabilities assumed either individually or as part of a group of liabilities, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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