Shareholders' Deficit - Summary of Changes in Shareholders' Deficit (Parenthetical) (Detail) - USD ($) shares in Millions, $ in Millions |
3 Months Ended | 6 Months Ended | ||
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Jun. 30, 2019 |
Jun. 30, 2018 |
Jun. 30, 2019 |
Jun. 30, 2018 |
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| Equity [Abstract] | ||||
| Issuance of common shares | 0.2 | 1.2 | 0.6 | 3.9 |
| Repurchases of common shares | 0.1 | 12.0 | 0.2 | 13.1 |
| Forward Counterparties' delivery of common shares to the Company | 8.4 | 2.0 | 8.4 | |
| Foreign currency translation adjustment, tax | $ (1.5) | $ (3.1) | $ (1.0) | $ (2.0) |
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- Definition Shares repurchased and retired under forward purchasing transactions. No definition available.
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- References No definition available.
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- Definition Amount of tax expense (benefit), after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature, attributable to parent entity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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