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Operations and Significant Accounting Policies - Lease Maturities (Details) - USD ($)
$ in Millions

Dec. 31, 2019

Dec. 31, 2018

Leases Maturities [Abstract]

2020

$ 6.6

2021

6.0

2022

5.0

2023

3.2

2024

2.9

Thereafter

11.5

Total Lease Payments Due

35.2

Less: Imputed Interest

6.5

Total Lease Obligations

28.7

Less: Current Lease Obligations

^[1]

6.9

$ 0.0

Long-term Lease Obligations

^[2]

$ 21.8

$ 0.0

[1]	See Leases.
[2]	See Leases.

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Leases Maturities [Abstract]

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Amount of lessee's undiscounted obligation for lease payments for operating lease.

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