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Share and Unit-based Plans - Schedule of LTIP Grants (Details) - $ / shares | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
LTIP units |  |  |
Share and unit-based plans [Line Items] |  |  |
Granted (in shares) | 552,866 | 343,431 | 569,136
Granted (in dollars per share) | $ 26.59 | $ 32.40 | $ 51.78
January 1, 2018 | Service-based | First vesting period |  |  |
Share and unit-based plans [Line Items] |  |  |
Granted (in shares) |  |  | 65,466
Granted (in dollars per share) |  |  | $ 65.68
January 1, 2018 | Market-indexed | First vesting period |  |  |
Share and unit-based plans [Line Items] |  |  |
Granted (in shares) |  |  | 291,326
Granted (in dollars per share) |  |  | $ 44.28
January 29, 2018 | Service-based | First vesting period |  |  |
Share and unit-based plans [Line Items] |  |  |
Granted (in shares) |  |  | 1,893
Granted (in dollars per share) |  |  | $ 66.02
January 29, 2018 | Service-based | Second vesting period |  |  |
Share and unit-based plans [Line Items] |  |  |
Granted (in shares) |  |  | 13,632
Granted (in dollars per share) |  |  | $ 66.02
January 29, 2018 | Market-indexed | First vesting period |  |  |
Share and unit-based plans [Line Items] |  |  |
Granted (in shares) |  |  | 7,775
Granted (in dollars per share) |  |  | $ 48.23
March 2, 2018 | Service-based | Third vesting period |  |  |
Share and unit-based plans [Line Items] |  |  |
Granted (in shares) |  |  | 99,407
Granted (in dollars per share) |  |  | $ 59.04
April 26, 2018 | Service-based | Fourth vesting period |  |  |
Share and unit-based plans [Line Items] |  |  |
Granted (in shares) |  |  | 89,637
Granted (in dollars per share) |  |  | $ 55.78
January 1, 2019 | Service-based | First vesting period |  |  |
Share and unit-based plans [Line Items] |  |  |
Granted (in shares) |  | 81,732 |
Granted (in dollars per share) |  | $ 43.28 |
January 1, 2019 | Market-indexed | First vesting period |  |  |
Share and unit-based plans [Line Items] |  |  |
Granted (in shares) |  | 250,852 |
Granted (in dollars per share) |  | $ 29.25 |
September 1, 2019 | Service-based | First vesting period |  |  |
Share and unit-based plans [Line Items] |  |  |
Granted (in shares) |  | 4,393 |
Granted (in dollars per share) |  | $ 28.53 |
September 1, 2019 | Market-indexed | First vesting period |  |  |
Share and unit-based plans [Line Items] |  |  |
Granted (in shares) |  | 6,454 |
Granted (in dollars per share) |  | $ 19.42 |
January 1, 2020 | Service-based | First vesting period |  |  |
Share and unit-based plans [Line Items] |  |  |
Granted (in shares) | 154,158 |  |
Granted (in dollars per share) | $ 26.92 |  |
January 1, 2020 | Market-indexed | First vesting period |  |  |
Share and unit-based plans [Line Items] |  |  |
Granted (in shares) | 321,940 |  |
Granted (in dollars per share) | $ 27.80 |  |
March 1, 2020 | Service-based | First vesting period |  |  |
Share and unit-based plans [Line Items] |  |  |
Granted (in shares) | 39,176 |  |
Granted (in dollars per share) | $ 20.42 |  |
March 1, 2020 | Market-indexed | First vesting period |  |  |
Share and unit-based plans [Line Items] |  |  |
Granted (in shares) | 37,592 |  |
Granted (in dollars per share) | $ 21.28 |  |

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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=120381028&loc=d3e5070-113901 + Details
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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued 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=120381028&loc=d3e5070-113901 + Details
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