Share-Based Compensation - Share-Based Compensation Expense and Cash Flows (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Payment Arrangement [Abstract]
Share-based compensation expense	$ 10.0	$ 13.5	$ 38.3
Tax benefit	0.0	0.0	0.0
Share-based compensation expense, net of tax benefit	10.0	13.5	38.3
Cash received upon the exercise of stock options	0.0	0.0	0.0
Write-off tax benefits related to share-based compensation	$ 0.0	$ 0.0	$ 0.0

Share Based Compensation Expense Net of Tax.

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- Definition

Write-Off Tax Benefits Related To Share-Based Compensation

+ References

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- References

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Amount of tax benefit for recognition of expense of 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 (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Amount of cash inflow from exercise of option under share-based payment arrangement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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Amount of noncash expense for share-based payment arrangement.

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