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CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Parenthetical) - CAD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Statement of comprehensive income [abstract] |  |  |
Unrealized income (loss), tax | $ 9 | $ 3 | $ 2
Reclassification to net earnings (loss), tax | $ 5 | $ 2 | $ 2

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- Definition Income Tax Relating To Reclassification Adjustments On Cash Flow Hedges Of Other Comprehensive Income + References No definition available. + Details
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