Share-Based Compensation - Narrative (Details) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($) $ / shares shares
Certain Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to unvested share awards outstanding \| $	$ 22.3
Unrecognized compensation cost, expected weighted average period	2 years 2 months 12 days
Employee share awards \| Certain Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in periods (in shares)	0.5
Fair value of units granted (in dollars per share) \| $ / shares	$ 24.74
Period of performance	3 years
Common stock, shares issued (in shares)	0.2
Shares paid for tax withholding (in shares)	0.1
Employee share awards \| Certain Employee \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of growth in earnings (in shares)	0.00%
Employee share awards \| Certain Employee \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of growth in earnings (in shares)	200.00%
Restricted Stock Units for Board Members \| Certain Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in periods (in shares)	0.2
Fair value of units granted (in dollars per share) \| $ / shares	$ 15.91
Period of performance	3 years
Restricted Stock Units for Board Members \| Board Members
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to unvested share awards outstanding \| $	$ 0.1
Unrecognized compensation cost, expected weighted average period	2 months 12 days

Share Based Compensation Arrangement By Share-based Payment Award, Percentage of Growth in Earnings

No definition available.

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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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=120381028&loc=d3e5070-113901

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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

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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

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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

Number of shares issued under share-based payment arrangement.

+ 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
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

+ References

No definition available.

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