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Shareholders' Equity - Shares Repurchased (Details) - USD ($) $ / shares in Units, $ in Millions | 1 Months Ended | 3 Months Ended | 4 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | ---
May 05, 2022 | Mar. 31, 2022 | Dec. 31, 2021 | Sep. 30, 2021 | Jun. 30, 2021 | Mar. 31, 2021 | May 05, 2022 | Dec. 31, 2021 | Feb. 23, 2022
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |
Repurchases of common stock |  | $ 152.0 |  |  |  | $ 77.0 |  |  |
Common Shares |  |  |  |  |  |  |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |
Repurchase authorized amount |  |  |  |  |  |  |  |  | $ 350.0
Shares repurchased (in shares) |  | 2,738,223 | 3,725,982 | 2,918,993 | 1,887,531 | 1,986,534 |  | 10,519,040 |
Repurchases of common stock |  | $ 155.0 | $ 191.0 | $ 140.0 | $ 88.0 | $ 77.0 |  | $ 496.0 |
Average price paid per share (in dollars per share) |  | $ 56.62 | $ 51.47 | $ 47.76 | $ 46.63 | $ 38.83 |  | $ 47.19 |
Settlement of prepaid share repurchases |  | $ 3.0 |  |  |  |  |  |  |
Common Shares | Subsequent Event |  |  |  |  |  |  |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |  |  |  |  |
Remaining capacity of shares repurchase program | $ 240.0 |  |  |  |  |  | $ 240.0 |  |
Shares repurchased (in shares) | 1,007,045 |  |  |  |  |  | 3,745,268 |  |
Repurchases of common stock | $ 61.0 |  |  |  |  |  | $ 216.0 |  |
Average price paid per share (in dollars per share) | $ 59.86 |  |  |  |  |  | $ 57.49 |  |

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition The cash outflow to reacquire common stock during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3291-108585 + Details
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- Definition Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=123467817&loc=d3e21463-112644 Reference 2: 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=120391452&loc=d3e13212-122682 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770 Reference 4: 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(28)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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