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Equity-Based Compensation (Schedule of Number of Awards and Weighted Average Grant Date Fair Value) (Details) - $ / shares |  | 1 Months Ended | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Dec. 31, 2021 | Feb. 28, 2017 | Mar. 31, 2021 | Sep. 30, 2019 | Sep. 30, 2018 | Dec. 31, 2019
Performance stock units |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Number of awards (in shares) |  |  |  | 183,908 | 135,540 |
Weighted average grant date fair value (in USD per share) |  |  |  | $ 40.49 | $ 33.60 |
Restricted stock units |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Number of awards (in shares) |  |  |  | 144,172 | 95,674 |
Weighted average grant date fair value (in USD per share) |  |  |  | $ 39.43 | $ 36.81 |
Deferred stock units |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Number of awards (in shares) |  |  |  | 7,509 | 10,255 |
Weighted average grant date fair value (in USD per share) |  |  |  | $ 37.95 | $ 35.96 |
Common shares |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Number of awards (in shares) |  |  |  | 7,509 | 2,113 |
Weighted average grant date fair value (in USD per share) |  |  |  | $ 37.95 | $ 35.50 |
Scenario, Forecast | Performance stock units |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Shares to be issued on conversion (in shares) | 38,488 |  |  |  |  | 145,420
2015 Incentive Plan | Performance stock units |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Shares to be issued on conversion as percentage of total award |  | 95.50% |  |  |  |
2015 Incentive Plan | Scenario, Forecast | Performance stock units |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Shares to be issued on conversion (in shares) |  |  | 126,337 |  |  |

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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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