| Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] |
The following table sets forth the changes in AOCI, net of tax, by component during the three and six months ended June 30, 2025 and June 30, 2024: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Foreign Currency Translation Gain (Loss) | | Net Actuarial Gain and Prior Service Cost | | Amortization of Gain on Interest Rate Swap | | Net Gain (Loss) on Marketable Securities Held in Trust | | Total | | Three Months Ended June 30, 2025 | | | | | | | | | | | Balance at March 31, 2025 | $ | (2,313.8) | | | $ | (22.0) | | | $ | 8.0 | | | $ | (6.7) | | | $ | (2,334.5) | | | Other comprehensive income (loss) | 231.0 | | | 0.3 | | | — | | | 10.0 | | | 241.3 | | | Tax (expense) benefit | 8.8 | | | (1.2) | | | — | | | (2.3) | | | 5.3 | | | Other comprehensive income (loss), net of tax | 239.8 | | | (0.9) | | | — | | | 7.7 | | | 246.6 | | | Other comprehensive income (loss) attributable to noncontrolling interest | (1.2) | | | — | | | — | | | — | | | (1.2) | | | Balance as of June 30, 2025 | $ | (2,075.2) | | | $ | (22.9) | | | $ | 8.0 | | | $ | 1.0 | | | $ | (2,089.1) | | | | | | | | | | | | | Three Months Ended June 30, 2024 | | | | | | | | | | | Balance at March 31, 2024 | $ | (2,059.1) | | | $ | (32.2) | | | $ | 8.1 | | | $ | (10.1) | | | $ | (2,093.3) | | | Other comprehensive income (loss) | (135.2) | | | 0.8 | | | — | | | (3.4) | | | (137.8) | | | Tax (expense) benefit | (1.3) | | | (0.2) | | | — | | | 0.8 | | | (0.7) | | | Other comprehensive income (loss), net of tax | (136.5) | | | 0.6 | | | — | | | (2.6) | | | (138.5) | | | Other comprehensive income (loss) attributable to noncontrolling interest | 2.4 | | | — | | | — | | | — | | | 2.4 | | | Balance as of June 30, 2024 | $ | (2,193.2) | | | $ | (31.6) | | | $ | 8.1 | | | $ | (12.7) | | | $ | (2,229.4) | | | | | | | | | | | | | Six Months Ended June 30, 2025 | | | | | | | | | | | Balance at December 31, 2024 | $ | (2,420.3) | | | $ | (22.1) | | | $ | 8 | | | $ | (14.6) | | | $ | (2,449) | | | Other comprehensive income (loss) | 340.1 | | | 0.5 | | | — | | | 20.3 | | | 360.9 | | | Tax (expense) benefit | 7.8 | | | (1.3) | | | — | | | (4.7) | | | 1.8 | | | Other comprehensive income (loss), net of tax | 347.9 | | | (0.8) | | | — | | | 15.6 | | | 362.7 | | | Other comprehensive income (loss) attributable to noncontrolling interest | (2.8) | | | — | | | — | | | — | | | (2.8) | | | Balance as of June 30, 2025 | $ | (2,075.2) | | | $ | (22.9) | | | $ | 8.0 | | | $ | 1.0 | | | $ | (2,089.1) | | | | | | | | | | | | | Six Months Ended June 30, 2024 | | | | | | | | | | | Balance at December 31, 2023 | $ | (1,930.2) | | | $ | (33.0) | | | $ | 8.1 | | | $ | 0.2 | | | $ | (1,954.9) | | | Other comprehensive income (loss) | (260.7) | | | 2.1 | | | — | | | (16.7) | | | (275.3) | | | Tax (expense) benefit | (5.5) | | | (0.7) | | | — | | | 3.8 | | | (2.4) | | | Other comprehensive income (loss), net of tax | (266.2) | | | 1.4 | | | — | | | (12.9) | | | (277.7) | | | Other comprehensive income (loss) attributable to noncontrolling interest | 3.2 | | | — | | | — | | | — | | | 3.2 | | | Balance as of June 30, 2024 | $ | (2,193.2) | | | $ | (31.6) | | | $ | 8.1 | | | $ | (12.7) | | | $ | (2,229.4) | |
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