| Comprehensive Income (Loss) Note [Text Block] |
Accumulated Other Comprehensive Income (Loss) (“AOCI”)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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