Supplemental Financial Data - Other Non-Current Assets (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Disclosure Text Block Supplement [Abstract]
Right of use assets	$ 72.9	$ 87.9
Prepaid pension assets	4.3	9.9
Investments	27.0	23.7
Other non-current assets	16.3	13.1
Total	$ 120.5	$ 134.6

Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

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The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

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Amount of other miscellaneous assets expected to be realized or consumed after one year or normal operating cycle, if longer.

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