Shareholders' Deficit - Summary of Changes in Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Sep. 30, 2020 |
Sep. 30, 2019 |
Sep. 30, 2020 |
Sep. 30, 2019 |
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| Accumulated Other Comprehensive Income (Loss) [Line Items] | ||||||||||||
| Beginning balance | $ (264.8) | $ (534.2) | $ (390.0) | $ (723.4) | ||||||||
| Other comprehensive income (loss) before reclassifications, net of tax | 20.1 | (24.2) | (14.7) | (19.9) | ||||||||
| Amounts reclassified from accumulated other comprehensive loss to income, net of tax | (3.7) | [1] | 0.2 | [1] | (2.5) | [2] | (0.7) | [2] | ||||
| Total other comprehensive income (loss) | 16.4 | (24.0) | (17.2) | (20.6) | ||||||||
| Ending balance | (912.9) | (467.5) | (912.9) | (467.5) | ||||||||
| Foreign Currency Translation Adjustments [Member] | ||||||||||||
| Accumulated Other Comprehensive Income (Loss) [Line Items] | ||||||||||||
| Beginning balance | (251.5) | (206.3) | (211.6) | (211.6) | ||||||||
| Other comprehensive income (loss) before reclassifications, net of tax | 19.5 | (24.0) | (20.4) | (18.7) | ||||||||
| Total other comprehensive income (loss) | 19.5 | (24.0) | (20.4) | (18.7) | ||||||||
| Ending balance | (232.0) | (230.3) | (232.0) | (230.3) | ||||||||
| Unrealized Gain (Loss) on Derivatives [Member] | ||||||||||||
| Accumulated Other Comprehensive Income (Loss) [Line Items] | ||||||||||||
| Beginning balance | 5.4 | (0.1) | (0.9) | 1.8 | ||||||||
| Other comprehensive income (loss) before reclassifications, net of tax | 0.6 | (0.2) | 5.7 | (1.2) | ||||||||
| Amounts reclassified from accumulated other comprehensive loss to income, net of tax | (3.7) | [1] | 0.2 | [1] | (2.5) | [2] | (0.7) | [2] | ||||
| Total other comprehensive income (loss) | (3.1) | 3.2 | (1.9) | |||||||||
| Ending balance | 2.3 | (0.1) | 2.3 | (0.1) | ||||||||
| Accumulated Other Comprehensive Loss [Member] | ||||||||||||
| Accumulated Other Comprehensive Income (Loss) [Line Items] | ||||||||||||
| Beginning balance | (246.1) | (206.4) | (212.5) | (209.8) | ||||||||
| Ending balance | $ (229.7) | $ (230.4) | $ (229.7) | $ (230.4) | ||||||||
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