Share Capital - PSUs (Narrative) (Details) - PSUs - shares	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Vested and will be settled in cash (in shares)	2,400,000	2,700,000
Award subject to targets relating to total shareholder return (as a percent)	50.00%
Award subject to targets relating to net asset value (as a percent)	25.00%
Net present value discount rate	10.00%
Award subject to targets relating to execution of corporate strategy (as a percent)	25.00%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of PSUs that vest (as a percent)	0.00%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of PSUs that vest (as a percent)	200.00%

Award Vesting Percentage Subject to Targets Relating to Net Asset Value

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- Definition

Award Vesting Percentage Subject to Targets Relating to Total Shareholder Return

+ References

No definition available.

+ Details

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- Definition

Award Vesting Percentage Subject to Targets Relating to the Execution of Corporate Strategy

+ References

No definition available.

+ Details

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- Definition

Net Asset Valuation, Discount Rate

+ References

No definition available.

+ Details

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Vested And Exercisable

+ References

No definition available.

+ Details

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ 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 (a)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&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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- Definition

Percentage of vesting of award under share-based payment arrangement.

+ References

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