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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, 2020 $ / shares | Dec. 31, 2019 $ / shares | Dec. 31, 2018 $ / shares
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 | 897.00 | 925.00 | 950.00
Number of options, Options granted | 0 |  | 0
Number of options, Options exercised | (448.50) | 0 | 0
Number of options, Options forfeited | (21.00) | (28.00) | (25.00)
Number of options, Options outstanding at end of the year | 427.50 | 897.00 | 925.00
Number of options, Option exercisable at end of the year | 213.75 | 448.50 | 0
Weighted-average exercise price, Options outstanding at beginning of the year | $ 135.60 | $ 140.60 | $ 147.00
Weighted average exercise price, Options granted | 0 |  | 0
Weighted average exercise price, Options exercised | 135.60 | 0 | 0
Weighted average exercise price, Options forfeited | 0 | 0 | 0
Weighted-average exercise price, Options outstanding at end of the year | 132.70 | 135.60 | 140.60
Weighted average exercise price, Option exercisable at end of the year | $ 132.70 | $ 135.60 | $ 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 | 314.25 | 882.75 | 1,936.00
Number of options, Options granted | 0 |  | 0
Number of options, Options exercised | (314.25) | (547.25) | (1,027.25)
Number of options, Options forfeited | 0 | (21.25) | (26.00)
Number of options, Options outstanding at end of the year | 0 | 314.25 | 882.75
Number of options, Option exercisable at end of the year | 0 | 314.25 | 416.50
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, Options exercised | 34.40 | 34.40 | 34.40
Weighted average exercise price, Options forfeited | 0 | 0 | 0
Weighted-average exercise price, Options outstanding at end of the year | 0 | 34.40 | 34.40
Weighted average exercise price, Option exercisable at end of the year | $ 0 | $ 34.40 | $ 34.40
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 | 46.00 | 50.00 | 0
Number of options, Options granted | 0 |  | 50.00
Number of options, Options exercised | (21.00) | 0 | 0
Number of options, Options forfeited | (4.00) | (4.00) | 0
Number of options, Options outstanding at end of the year | 21.00 | 46.00 | 50.00
Number of options, Option exercisable at end of the year | 0 | 0 | 0
Weighted-average exercise price, Options outstanding at beginning of the year | $ 141.70 | $ 147.00 | $ 0
Weighted average exercise price, Options granted | 0 |  | 147.00
Weighted average exercise price, Options exercised | 138.70 | 0 | 0
Weighted average exercise price, Options forfeited | 0 | 0 | 0
Weighted-average exercise price, Options outstanding at end of the year | 138.70 | 141.70 | 147.00
Weighted average exercise price, Option exercisable at end of the year | $ 0 | $ 0 | $ 0
Granted on November 13, 2020 [Member] |  |  |
Disclosure of terms and conditions of share-based payment arrangement [Line Items] |  |  |
Number of options, Options outstanding at beginning of the year | 0 |  |
Number of options, Options granted | 200 |  |
Number of options, Options exercised | 0 |  |
Number of options, Options forfeited | 0 |  |
Number of options, Options outstanding at end of the year | 200.00 | 0 |
Number of options, Option exercisable at end of the year | 0 |  |
Weighted-average exercise price, Options outstanding at beginning of the year | $ 0 |  |
Weighted average exercise price, Options granted | 206.00 |  |
Weighted average exercise price, Options exercised | 0 |  |
Weighted average exercise price, Options forfeited | 0 |  |
Weighted-average exercise price, Options outstanding at end of the year | 206.00 | $ 0 |
Weighted average exercise price, Option exercisable at end of the year | $ 0 |  |

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- Definition The weighted average exercise price of share options exercisable in a share-based payment arrangement. [Refer: Weighted average [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2020-01-01 -Paragraph 45 -Subparagraph b -Clause vii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45_b_vii&doctype=Standard -URIDate 2020-01-01 + Details
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