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Pension Plans and Other Benefits - Plan Asset FV Measurements - USD ($) $ in Millions | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Defined Benefit Plan Disclosure |  |  |
Fair value of asset |  | $ 845.2 | $ 790.6
Fair Value Inputs Level 1 |  |  |
Defined Benefit Plan Disclosure |  |  |
Fair value of asset |  | 4.6 | 3.4
Fair Value Inputs Level 2 |  |  |
Defined Benefit Plan Disclosure |  |  |
Fair value of asset |  | 839.5 | 785.7
Fair Value Inputs Level 3 |  |  |
Defined Benefit Plan Disclosure |  |  |
Fair value of asset |  | $ 1.1 | $ 1.5
Debt Security, Corporate, US |  |  |
Defined Benefit Plan Disclosure |  |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage |  | 48.00% | 46.00%
US and Canada Government Debt Securities |  |  |
Defined Benefit Plan Disclosure |  |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage |  | 45.00% | 49.00%
Canadian Equity Securities |  |  |
Defined Benefit Plan Disclosure |  |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage |  | 0.00% | 18.00%
Cash And Cash Equivalents |  |  |
Defined Benefit Plan Disclosure |  |  |
Fair value of asset |  | $ 4.6 | $ 3.4
Cash And Cash Equivalents | Fair Value Inputs Level 1 |  |  |
Defined Benefit Plan Disclosure |  |  |
Fair value of asset |  | 4.6 | 3.4
Cash And Cash Equivalents | Fair Value Inputs Level 2 |  |  |
Defined Benefit Plan Disclosure |  |  |
Fair value of asset |  | 0.0 | 0.0
Cash And Cash Equivalents | Fair Value Inputs Level 3 |  |  |
Defined Benefit Plan Disclosure |  |  |
Fair value of asset |  | 0.0 | 0.0
Equity Securities |  |  |
Defined Benefit Plan Disclosure |  |  |
Fair value of asset | [1] | 198.5 | 216.4
Equity Securities | Fair Value Inputs Level 1 |  |  |
Defined Benefit Plan Disclosure |  |  |
Fair value of asset | [1] | 0.0 | 0.0
Equity Securities | Fair Value Inputs Level 2 |  |  |
Defined Benefit Plan Disclosure |  |  |
Fair value of asset | [1] | 198.5 | 216.4
Equity Securities | Fair Value Inputs Level 3 |  |  |
Defined Benefit Plan Disclosure |  |  |
Fair value of asset | [1] | 0.0 | 0.0
Fixed Income Securities |  |  |
Defined Benefit Plan Disclosure |  |  |
Fair value of asset | [2] | 641.0 | 569.3
Fixed Income Securities | Fair Value Inputs Level 1 |  |  |
Defined Benefit Plan Disclosure |  |  |
Fair value of asset | [2] | 0.0 | 0.0
Fixed Income Securities | Fair Value Inputs Level 2 |  |  |
Defined Benefit Plan Disclosure |  |  |
Fair value of asset | [2] | 641.0 | 569.3
Fixed Income Securities | Fair Value Inputs Level 3 |  |  |
Defined Benefit Plan Disclosure |  |  |
Fair value of asset | [2] | 0.0 | 0.0
Private Equity Funds |  |  |
Defined Benefit Plan Disclosure |  |  |
Fair value of asset |  | 1.1 | 1.5
Private Equity Funds | Fair Value Inputs Level 1 |  |  |
Defined Benefit Plan Disclosure |  |  |
Fair value of asset |  | 0.0 | 0.0
Private Equity Funds | Fair Value Inputs Level 2 |  |  |
Defined Benefit Plan Disclosure |  |  |
Fair value of asset |  | 0.0 | 0.0
Private Equity Funds | Fair Value Inputs Level 3 |  |  |
Defined Benefit Plan Disclosure |  |  |
Fair value of asset |  | $ 1.1 | $ 1.5
Other Foreign |  |  |
Defined Benefit Plan Disclosure |  |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage |  |  | 47.00%
U.S. Government Bonds |  |  |
Defined Benefit Plan Disclosure |  |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage |  | 43.00% | 35.00%
Debt Security, Corporate, Non-US |  |  |
Defined Benefit Plan Disclosure |  |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage |  | 7.00% | 5.00%
[1] | This class, which includes several funds, was invested approximately 43% in U.S. equity securities, 0% in Canadian equity securities and 57% in other international equity securities as of December 31, 2020, and 35% in U.S. equity securities, 18% in Canadian equity securities and 47% in other international equity securities as of December 31, 2019.
[2] | This class, which includes several funds, was invested approximately 48% in corporate debt securities, 45% in governmental securities in the U.S. and Canada and 7% in other foreign entity debt securities as of December 31, 2020, and 46% in corporate debt securities, 49% in governmental securities in the U.S. and Canada and 5% in other foreign entity debt securities as of December 31, 2019.

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