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STOCK COMPENSATION - Restricted Stock Units Narrative (Details) - Restricted Stock Units (RSUs) - USD ($) $ / shares in Units, shares in Millions, $ in Millions | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Equity instrument granted in period, weighted average grant date fair value (in dollars per share) | $ 59.56 | $ 67.60 | $ 50.44
Award requisite service period | 3 years |  |
Total unrecognized compensation cost related to award, weighted average period | 16 months |  |
Restricted stock units, unvested (in shares) | 1.1 | 1.2 |
Equity instrument, granted (in shares) | 0.5 |  |
Vested or forfeited (in shares) | 0.6 |  |
Total compensation cost for award recognized in income | $ 32 | $ 29 | $ 28
Total compensation cost for award recognized in income, tax benefit | $ 8 | $ 8 | $ 7
One-year vesting period |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Total unrecognized compensation cost related to award, weighted average period | 1 year |  |
Two-year vesting period |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Total unrecognized compensation cost related to award, weighted average period | 2 years |  |
Three-year vesting period |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Total unrecognized compensation cost related to award, weighted average period | 3 years |  |

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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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