Quarterly report pursuant to Section 13 or 15(d)

Shareholders' Deficit - Summary of Changes in Shareholders' Deficit (Parenthetical) (Detail)

v3.19.2
Shareholders' Deficit - Summary of Changes in Shareholders' Deficit (Parenthetical) (Detail) - USD ($)
shares in Millions, $ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
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)