Shareholders' Equity - Unrecognized Compensation Cost (Details) $ in Millions	12 Months Ended
Dec. 31, 2020 USD ($)
Equity [Abstract]
Total unrecognized compensation cost related to unvested share-based payment awards	$ 16.6
Period for recognition of unrecognized compensation cost related to unvested share-based payment awards	1 year 1 month 6 days
Year Ended December 31,
2021	$ 8.9
2022	6.1
2023	1.6
2024	0.0
2025	0.0
Total	$ 16.6

Unrecognized compensation cost expected to be recognized in year five of the five succeeding years.

No definition available.

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- Definition

Unrecognized compensation cost expected to be recognized in year four of the five succeeding years.

+ References

No definition available.

+ Details

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- Definition

Unrecognized compensation cost expected to be recognized in year one of the five succeeding years.

+ References

No definition available.

+ Details

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- Definition

Unrecognized compensation cost expected to be recognized in year three of the five succeeding years.

+ References

No definition available.

+ Details

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- Definition

Unrecognized compensation cost expected to be recognized in year two of the five succeeding years.

+ References

No definition available.

+ Details

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- Definition

Amount of cost not yet recognized for nonvested award 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
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

+ Details

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- 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

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- References

No definition available.

+ Details

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