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Capital Stock (Tables) | 12 Months Ended
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Dec. 31, 2020
Equity [Abstract] |
Summary of Normal Course Issuer Bids | The following is a summary of the Normal Course Issuer Bids [number of shares in the table below are expressed in whole numbers]:
|  | 2020 |  |  | 2019 |
|  | Shares purchased |  |  | Cash amount |  |  | Shares purchased |  |  | Cash amount |
2018 Bid |  |  | 0 |  |  | $ | 0 |  |  |  | 23,401,457 |  |  | $ | 1,159 |
2019 Bid |  |  | 5,077,882 |  |  |  | 203 |  |  |  | 2,367,106 |  |  |  | 130 |
|  |  | 5,077,882 |  |  | $ | 203 |  |  |  | 25,768,563 |  |  | $ | 1,289 |
Maximum Number of Shares Outstanding Exercised or Converted |
[c] | The following table presents the maximum number of shares that would be outstanding if all the dilutive instruments outstanding at March 4, 2021 were exercised or converted:
Common Shares |  |  | 301,877,555 |
Stock options [i] |  |  | 6,968,787 |
|  |  | 308,846,342 |
| [i] | Options to purchase Common Shares are exercisable by the holder in accordance with the vesting provisions and upon payment of the exercise price as may be determined from time to time pursuant to the Company’s stock option plans.

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- Definition Tabular disclosure of an entity's capital units or capital shares, including the value of capital units or capital shares, units authorized, units outstanding and other information necessary to a fair presentation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-04.16) -URI http://asc.fasb.org/extlink&oid=120401414&loc=d3e603758-122996 + Details
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