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ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2024 | Jun. 30, 2024 | Mar. 31, 2024 | Sep. 30, 2023 | Jun. 30, 2023 | Mar. 31, 2023 | Sep. 30, 2024 | Sep. 30, 2023
Changes in accumulated other comprehensive income (loss) by component, net of taxes |  |  |  |  |  |  |  |
Balance at the beginning of the period | $ 2,398.5 | $ 2,373.8 | $ 2,400.7 | $ 2,290.0 | $ 2,270.3 | $ 2,296.9 | $ 2,400.7 | $ 2,296.9
Other adjustments | 1.0 |  |  | (0.6) |  |  | 0.5 | 0.1
Balance at the end of the period | 2,556.7 | 2,398.5 | 2,373.8 | 2,390.3 | 2,290.0 | 2,270.3 | 2,556.7 | 2,390.3
Pensions |  |  |  |  |  |  |  |
Changes in accumulated other comprehensive income (loss) by component, net of taxes |  |  |  |  |  |  |  |
Balance at the beginning of the period | (20.1) | (20.2) | (20.3) | (25.3) | (25.5) | (25.8) | (20.3) | (25.8)
Amortization of net gain (loss) |  | 0.1 | 0.1 | 0.2 | 0.2 | 0.3 |  |
Balance at the end of the period | (20.1) | (20.1) | (20.2) | (25.1) | (25.3) | (25.5) | (20.1) | (25.1)
Post Retirement |  |  |  |  |  |  |  |
Changes in accumulated other comprehensive income (loss) by component, net of taxes |  |  |  |  |  |  |  |
Balance at the beginning of the period | 9.3 | 10.1 | 11.0 | 16.5 | 17.6 | 18.7 | 11.0 | 18.7
Amortization of prior service cost | (0.7) | (0.7) | (0.7) | (0.7) | (0.7) | (0.7) |  |
Amortization of net gain (loss) | (0.1) | (0.1) | (0.2) | (0.3) | (0.4) | (0.4) |  |
Balance at the end of the period | 8.5 | 9.3 | 10.1 | 15.5 | 16.5 | 17.6 | 8.5 | 15.5
Non-Qualified Plans |  |  |  |  |  |  |  |
Changes in accumulated other comprehensive income (loss) by component, net of taxes |  |  |  |  |  |  |  |
Balance at the beginning of the period | (0.2) | (0.2) | (0.2) | 0.1 | 0.1 | 0.1 | (0.2) | 0.1
Balance at the end of the period | (0.2) | (0.2) | (0.2) | 0.1 | 0.1 | 0.1 | (0.2) | 0.1
Other |  |  |  |  |  |  |  |
Changes in accumulated other comprehensive income (loss) by component, net of taxes |  |  |  |  |  |  |  |
Balance at the beginning of the period | 0.8 | 0.5 | 1.3 | 0.8 | 1.5 | 0.1 | 1.3 | 0.1
Foreign currency exchange | 1.0 | 0.3 | (0.9) | (0.6) | (0.7) | (0.3) |  |
Other adjustments |  |  | 0.1 |  |  | 1.7 |  |
Balance at the end of the period | 1.8 | 0.8 | 0.5 | 0.2 | 0.8 | 1.5 | 1.8 | 0.2
Accumulated Other Comprehensive Income (Loss) |  |  |  |  |  |  |  |
Changes in accumulated other comprehensive income (loss) by component, net of taxes |  |  |  |  |  |  |  |
Balance at the beginning of the period | (10.2) | (9.8) | (8.2) | (7.9) | (6.3) | (6.9) | (8.2) | (6.9)
Amortization of prior service cost | (0.7) | (0.7) | (0.7) | (0.7) | (0.7) | (0.7) |  |
Amortization of net gain (loss) | (0.1) |  | (0.1) | (0.1) | (0.2) | (0.1) |  |
Foreign currency exchange | 1.0 | 0.3 | (0.9) | (0.6) | (0.7) | (0.3) |  |
Other adjustments |  |  | 0.1 |  |  | 1.7 |  |
Balance at the end of the period | $ (10.0) | $ (10.2) | $ (9.8) | $ (9.3) | $ (7.9) | $ (6.3) | $ (10.0) | $ (9.3)

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