Significant Accounting Policies Cash and Cash Equivalents (Details) - USD ($) $ in Millions	Feb. 23, 2022	Dec. 31, 2021	Dec. 31, 2020
Significant Accounting Policies [Abstract]
Restricted Cash and Cash Equivalents		$ 16.0	$ 17.3
Restricted Cash and Cash Equivalents, Current		0.9	1.1
Restricted Cash and Cash Equivalents, Noncurrent		15.1	$ 16.2
Cash, FDIC Insured Limit		0.3
Cash, Uninsured Amount	$ 12.4	$ 37.5

Significant Accounting Policies [Abstract]

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- Definition

The amount of cash deposited in financial institutions as of the balance sheet date that is insured by the Federal Deposit Insurance Corporation.

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The amount of cash as of the balance sheet date that is not insured by the Federal Deposit Insurance Corporation.

+ References

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Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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