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Share-based Payments Arrangement - CHIEF's Outstanding Stock Options (Detail) - CHIEF Telecom Inc. (CHIEF) [Member] | 12 Months Ended
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Dec. 31, 2019 $ / shares | Dec. 31, 2018 $ / shares | Dec. 31, 2017 $ / shares
Granted on October 31, 2018 [Member] |  |  |
Disclosure of terms and conditions of share-based payment arrangement [Line Items] |  |  |
Number of options, Options outstanding at beginning of the year | 50.00 | 0 |
Number of options, Options granted |  | 50.00 |
Number of options, Options exercised | 0 | 0 |
Number of options, Options forfeited | (4.00) | 0 |
Number of options, Options outstanding at end of the year | 46.00 | 50.00 | 0
Number of options, Option exercisable at end of the year | 0 | 0 |
Weighted-average exercise price, Options outstanding at beginning of the year | $ 147.00 | $ 0 |
Weighted average exercise price, Options granted |  | 147.00 |
Weighted average exercise price of share options exercised in share-based payment arrangement | 0 | 0 |
Weighted average exercise price, Options forfeited | 0 | 0 |
Weighted-average exercise price, Options outstanding at end of the year | 141.70 | 147.00 | $ 0
Weighted average exercise price, Option exercisable at end of the year | $ 0 | $ 0 |
Granted on December 19, 2017 [Member] |  |  |
Disclosure of terms and conditions of share-based payment arrangement [Line Items] |  |  |
Number of options, Options outstanding at beginning of the year | 925.00 | 950.00 | 0
Number of options, Options granted |  | 0 | 950.00
Number of options, Options exercised | 0 | 0 |
Number of options, Options forfeited | (28.00) | (25.00) | 0
Number of options, Options outstanding at end of the year | 897.00 | 925.00 | 950.00
Number of options, Option exercisable at end of the year | 448.50 | 0 | 0
Weighted-average exercise price, Options outstanding at beginning of the year | $ 140.60 | $ 147.00 | $ 0
Weighted average exercise price, Options granted |  | 0 | 147.00
Weighted average exercise price of share options exercised in share-based payment arrangement | 0 | 0 |
Weighted average exercise price, Options forfeited | 0 | 0 | 0
Weighted-average exercise price, Options outstanding at end of the year | 135.60 | 140.60 | 147.00
Weighted average exercise price, Option exercisable at end of the year | $ 135.60 | $ 0 | $ 0
Granted on October 22, 2015 [Member] |  |  |
Disclosure of terms and conditions of share-based payment arrangement [Line Items] |  |  |
Number of options, Options outstanding at beginning of the year | 882.75 | 1,936.00 | 1,948.00
Number of options, Options granted |  | 0 | 0
Number of options, Options exercised | (547.25) | (1,027.25) |
Number of options, Options forfeited | (21.25) | (26.00) | (12.00)
Number of options, Options outstanding at end of the year | 314.25 | 882.75 | 1,936.00
Number of options, Option exercisable at end of the year | 314.25 | 416.50 | 968.00
Weighted-average exercise price, Options outstanding at beginning of the year | $ 34.40 | $ 34.40 | $ 34.40
Weighted average exercise price, Options granted |  | 0 | 0
Weighted average exercise price of share options exercised in share-based payment arrangement | 34.40 | 34.40 |
Weighted average exercise price, Options forfeited | 0 | 0 | 0
Weighted-average exercise price, Options outstanding at end of the year | 34.40 | 34.40 | 34.40
Weighted average exercise price, Option exercisable at end of the year | $ 34.40 | $ 34.40 | $ 34.40

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- Definition The number of share options outstanding in a share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2019-01-01 -Paragraph 45 -Subparagraph d -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2019-en-r&anchor=para_45_d&doctype=Standard -URIDate 2019-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2019-01-01 -Paragraph 45 -Subparagraph b -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2019-en-r&anchor=para_45_b_i&doctype=Standard -URIDate 2019-03-27 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2019-01-01 -Paragraph 45 -Subparagraph b -Clause vi -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2019-en-r&anchor=para_45_b_vi&doctype=Standard -URIDate 2019-03-27 + Details
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