XML 118 R104.htm IDEA: XBRL DOCUMENT v3.10.0.1
Income Taxes - Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits (Detail) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Schedule of Unrecognized Tax Benefits [Line Items]      
Unrecognized tax benefits — beginning of year $ 87.5 $ 58.2 $ 38.2
Gross additions — current year tax positions 9.1 31.0 10.7
Gross additions — prior year tax positions 9.3 10.9 10.4
Gross additions (reductions) — purchase accounting adjustments 1.0 4.0 9.7
Gross reductions — prior year tax positions (14.5) (9.4) (9.8)
Gross reductions — settlements with taxing authorities (8.9) (7.2) (1.0)
Unrecognized tax benefits — end of year $ 83.5 $ 87.5 $ 58.2