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Share and Unit-based Plans - Schedule LTIP Units Valuation Assumptions (Details) - LTIP units	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
January 1, 2018
Share and unit-based plans [Line Items]
Risk Free Interest Rate			1.98%
Expected Volatility			23.38%
January 29, 2018
Share and unit-based plans [Line Items]
Risk Free Interest Rate			2.25%
Expected Volatility			23.86%
January 1, 2019
Share and unit-based plans [Line Items]
Risk Free Interest Rate		2.46%
Expected Volatility		23.52%
September 1, 2019
Share and unit-based plans [Line Items]
Risk Free Interest Rate		1.42%
Expected Volatility		24.91%
January 1, 2020
Share and unit-based plans [Line Items]
Risk Free Interest Rate	1.62%
Expected Volatility	26.08%
March 1, 2020
Share and unit-based plans [Line Items]
Risk Free Interest Rate	0.85%
Expected Volatility	28.34%

X

- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ 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 (f)(2)(ii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

+ 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 (f)(2)(iv)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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.

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