Share-Based Compensation - Narrative (Details) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021 USD ($) installment shares	Jun. 30, 2021 USD ($) installment $ / shares shares
Certain Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost \| $	$ 19.1	$ 19.1
Unrecognized contractual term		2 years
Performance shares \| 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
Performance shares \| Certain Employee \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target achievement (in shares)		0.00%
Performance shares \| Certain Employee \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target achievement (in shares)		200.00%
Restricted Stock Units \| 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 \| Board Members
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in periods (in shares)	0.1	0.1
Fair value of units granted (in dollars per share) \| $ / shares		$ 17.35
Common stock, shares issued (in shares)	0.1	0.1
Unrecognized compensation cost \| $	$ 0.8	$ 0.8
Unrecognized contractual term		10 months 24 days
Number of annual installments \| installment	3	3

Share-based Compensation Arrangement by Share-based Payment Award, Number of Annual Installments

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- Definition

Share Based Compensation Arrangement By Share-based Payment Award, Percentage of Target Achievement

+ References

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

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-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
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-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

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- Definition

Number of shares issued under share-based payment arrangement.

+ References

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-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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