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LONG-TERM INCENTIVE PLANS - Restricted Shares and Performance Shares (Details) - Restricted Shares and Performance Shares - EquityInstruments | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
LONG-TERM INCENTIVE PLANS |  |  |
Balance, beginning of year | 20,433,491 | 12,525,256 | 10,086,234
Granted | 3,170,952 | 13,357,922 | 9,098,389
Forfeited | (1,901,782) | (3,046,593) | (2,717,724)
Exercised | (2,727,577) | (2,403,094) | (3,941,643)
Balance, end of year | 18,975,084 | 20,433,491 | 12,525,256
Grace period | 3 years |  |

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- Definition Period from grant date that an equity-based award expires, 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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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. + References No definition available. + Details
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- Definition The number of other equity instruments (ie other than share options) granted in a share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2017-01-01 -Paragraph 47 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2017-03-01&anchor=para_47_b&doctype=Standard -URIDate 2017-03-09 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 2 -IssueDate 2017-01-01 -Paragraph 45 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2017-03-01&anchor=para_45&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition The number of other equity instruments (ie other than share options) exercised or vested in a share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 2 -IssueDate 2017-01-01 -Paragraph 45 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2017-03-01&anchor=para_45&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition The number of other equity instruments (ie other than share options) forfeited in a share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 2 -IssueDate 2017-01-01 -Paragraph 45 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2017-03-01&anchor=para_45&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition The number of other equity instruments (ie other than share options) outstanding in a share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 2 -IssueDate 2017-01-01 -Paragraph 45 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2017-03-01&anchor=para_45&doctype=Standard -URIDate 2017-03-09 + Details
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