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Dividends and Distributions (Details) - USD ($) $ / shares in Units, $ in Thousands | 1 Months Ended | 2 Months Ended | 3 Months Ended | 5 Months Ended | 11 Months Ended
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May 31, 2021 | Mar. 31, 2021 | Dec. 31, 2020 | May 31, 2020 | Mar. 31, 2020 | Dec. 31, 2019 | Mar. 31, 2019 | Oct. 31, 2021 | Apr. 30, 2021 | Jan. 31, 2021 | Oct. 31, 2020 | Apr. 30, 2020 | Jan. 31, 2020 | Apr. 30, 2019 | Jul. 31, 2021 | Jul. 31, 2020 | Jul. 31, 2019 | Apr. 30, 2020 | Oct. 31, 2021
Dividends Payable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividend Per Share (in USD per share) |  |  |  |  |  |  |  |  | $ 0.22 | $ 0.21 | $ 0.21 | $ 0.21 | $ 0.20 |  | $ 0.22 |  | $ 0.21 |  |
Common Shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Distributions Declared |  |  |  |  |  |  |  |  | $ 56,029 | $ 0 | $ 43,282 | $ 42,568 | $ 0 |  | $ 57,897 |  | $ 43,271 | $ 129,121 |
Distributions Paid | $ 57,900 |  |  | $ 43,300 | $ 56,000 |  | $ 42,600 |  | 56,029 | 53,820 | $ 0 | $ 42,568 | 38,796 |  | 57,897 |  | $ 43,271 | $ 124,025 |
Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends Payable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividend Per Share (in USD per share) |  |  |  |  |  |  |  | $ 0.22 |  |  |  |  |  |  |  |  |  |  |
Common Shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Distributions Declared |  |  |  |  |  |  |  | $ 59,026 |  |  |  |  |  |  |  |  |  |  | $ 172,952
Distributions Paid |  |  |  |  |  |  |  | $ 0 |  |  |  |  |  |  |  |  |  |  | $ 168,538
Dividend equivalents accrued on unvested restricted stock units to be paid when the awards vest. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Distributions Paid | $ (178) | $ (179) | $ (693) | $ (232) |  | $ (169) | $ (233) |  |  |  |  |  |  |  |  |  |  |  |
Dividend equivalents paid on unvested restricted stock units that are not expected to vest (recognized as additional compensation). |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Distributions Paid |  |  |  |  |  |  |  |  | $ 7 | 6 |  |  | $ 4 | $ 10 | $ 6 | $ 10 |  |  |
Dividend equivalents paid on vested restricted stock units related to the market performance-based awards granted in 2018. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Distributions Paid |  |  |  |  |  |  |  |  |  | $ 1,823 |  |  |  |  |  |  |  |  |

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