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GOODWILL AND OTHER INTANGIBLE ASSETS Additional Information (Details) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2017 USD ($) reporting_units | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($)
Segment Reporting Information [Line Items] |  |  |  |
Goodwill and intangible assets |  | $ 1,100,000,000 | $ 1,100,000,000 |
Goodwill and intangible assets, percent of total assets |  | 19.00% | 20.00% |
Number of reporting units, operating performance below expectations | reporting_units | 2 |  |  |
Impairment of goodwill or indefinitely-lived intangible assets | $ 0 |  |  |
Amortization expense, intangible assets |  | $ 89,000,000 | $ 82,000,000 | $ 65,000,000
Canada |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Reporting unit, percentage of fair value in excess of carrying amount | 31.00% |  |  |
Other Businesses [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Reporting unit, percentage of fair value in excess of carrying amount | 15.00% |  |  |

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- Definition Intangible Assets Net Including Goodwill Percent Of Total Assets + References No definition available. + Details
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- Definition Number Of Reporting Units, Subject To Operating Performance Below Expectations + References No definition available. + Details
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- Definition The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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- Definition Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2420-110228 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 + Details
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- Definition Carrying amount of finite-lived intangible assets, indefinite-lived intangible assets and goodwill. Goodwill is an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Intangible assets are assets, not including financial assets, lacking physical substance. + References No definition available. + Details
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