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Share and Unit-based Plans - Schedule of LTIP Grants (Details) - $ / shares | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
LTIP units |  |  |
Share and unit-based plans |  |  |
Granted (shares) | 343,431 | 569,136 | 506,906
Granted (in dollars per share) | $ 32.40 | $ 51.78 | $ 55.33
Service-based |  |  |
Share and unit-based plans |  |  |
Granted (shares) | 343,431 | 569,136 | 506,906
January 1, 2017 | Service-based | First vesting period |  |  |
Share and unit-based plans |  |  |
Granted (shares) |  |  | 66,079
Granted (in dollars per share) |  |  | $ 70.84
January 1, 2017 | Market-indexed | First vesting period |  |  |
Share and unit-based plans |  |  |
Granted (shares) |  |  | 297,849
Granted (in dollars per share) |  |  | $ 47.15
March 3, 2017 | Service-based | Second vesting period |  |  |
Share and unit-based plans |  |  |
Granted (shares) |  |  | 134,742
Granted (in dollars per share) |  |  | $ 66.57
June 1, 2017 | Service-based | Third vesting period |  |  |
Share and unit-based plans |  |  |
Granted (shares) |  |  | 1,522
Granted (in dollars per share) |  |  | $ 58.31
June 1, 2017 | Market-indexed | Third vesting period |  |  |
Share and unit-based plans |  |  |
Granted (shares) |  |  | 6,714
Granted (in dollars per share) |  |  | $ 39.66
January 1, 2018 | Service-based | First vesting period |  |  |
Share and unit-based plans |  |  |
Granted (shares) |  | 65,466 |
Granted (in dollars per share) |  | $ 65.68 |
January 1, 2018 | Market-indexed | First vesting period |  |  |
Share and unit-based plans |  |  |
Granted (shares) |  | 291,326 |
Granted (in dollars per share) |  | $ 44.28 |
January 29, 2018 | Service-based | First vesting period |  |  |
Share and unit-based plans |  |  |
Granted (shares) |  | 1,893 |
Granted (in dollars per share) |  | $ 66.02 |
January 29, 2018 | Service-based | Second vesting period |  |  |
Share and unit-based plans |  |  |
Granted (shares) |  | 13,632 |
Granted (in dollars per share) |  | $ 66.02 |
January 29, 2018 | Market-indexed | First vesting period |  |  |
Share and unit-based plans |  |  |
Granted (shares) |  | 7,775 |
Granted (in dollars per share) |  | $ 48.23 |
March 2, 2018 | Service-based | Third vesting period |  |  |
Share and unit-based plans |  |  |
Granted (shares) |  | 99,407 |
Granted (in dollars per share) |  | $ 59.04 |
April 26, 2018 | Service-based | Fourth vesting period |  |  |
Share and unit-based plans |  |  |
Granted (shares) |  | 89,637 |
Granted (in dollars per share) |  | $ 55.78 |
January 1, 2019 | Service-based | First vesting period |  |  |
Share and unit-based plans |  |  |
Granted (shares) | 81,732 |  |
Granted (in dollars per share) | $ 43.28 |  |
January 1, 2019 | Market-indexed | First vesting period |  |  |
Share and unit-based plans |  |  |
Granted (shares) | 250,852 |  |
Granted (in dollars per share) | $ 29.25 |  |
September 1, 2019 | Service-based | First vesting period |  |  |
Share and unit-based plans |  |  |
Granted (shares) | 4,393 |  |
Granted (in dollars per share) | $ 28.53 |  |
September 1, 2019 | Market-indexed | First vesting period |  |  |
Share and unit-based plans |  |  |
Granted (shares) | 6,454 |  |
Granted (in dollars per share) | $ 19.42 |  |

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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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- 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=116856206&loc=d3e5070-113901 + Details
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