v3.19.3.a.u2

Common shares (Details) - USD ($) $ / shares in Units, $ in Millions |  | 2 Months Ended | 12 Months Ended
--- | --- | --- | ---
Dec. 17, 2019 | Feb. 26, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Common shares |  |  |  |  |
Common Stock, No Par Value |  |  | $ 0 | $ 0 |
Common Stock, Shares Authorized, Unlimited |  |  | Unlimited | Unlimited |
Common Stock, Shares, Issued |  |  | 108,675,294 | 108,341,738 |
Common Stock, Shares, Outstanding |  |  | 108,675,294 | 108,341,738 |
Stock Repurchase Program |  |  |  |  |
Common shares repurchased and canceled |  |  | $ 2.5 | $ 16.6 | $ 0.2
Common shares repurchased and canceled (in shares) |  |  | 1,064,081 | 7,772,971 |
Normal Course Issuer Bid [Member] |  |  |  |  |
Stock Repurchase Program |  |  |  |  |
Public float amount used to determine share amount, percent | 10.00% |  |  |  |
Normal Course Issuer Bid [Member] | Subsequent event |  |  |  |  |
Stock Repurchase Program |  |  |  |  |
Common shares repurchased and canceled |  | $ 4.1 |  |  |
Common shares repurchased and canceled (in shares) |  | 1,742,919 |  |  |
Normal Course Issuer Bid [Member] | Maximum |  |  |  |  |
Stock Repurchase Program |  |  |  |  |
Number of shares authorized for repurchase |  |  | 10,578,799 |  |
Number of shares that may be purchased per day |  |  | 9,243 |  |

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- Definition Face amount per share of no-par value common stock. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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