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SUPPLEMENTARY FINANCIAL STATEMENT INFORMATION - Cash Flow Information (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Disclosure Text Block [Abstract] |  |  |
Capital Additions | $ 483 | $ 690 | $ 395
Non-cash accruals | (86) | 15 | 94
Right-of-use asset - finance leases | 44 | 29 | 8
Grants | 0 | (10) | (3)
Cash paid for capital expenditures including deposits | 525 | 656 | 296
Taxes paid on income | 5 | 0 | 3
Income tax refunds | (120) | (118) | (11)
Interest paid on debt obligations net of capitalized interest | 170 | 98 | 106
Interest capitalized | $ 53 | $ 25 | $ 7

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- Definition The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121583591&loc=d3e4297-108586 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3536-108585 + Details
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- Definition Amount of cash paid for interest, excluding capitalized interest, classified as operating activity. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121583591&loc=d3e4297-108586 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 17 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3367-108585 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3536-108585 + Details
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