Income Taxes - Summary of Amount and Expiration Dates of Operating Loss and Tax Credit Carryforwards (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2015 USD ($)
Operating Loss And Tax Credit Carryforwards [Line Items]
Other	$ 3.6
Total	$ 1,266.1
Expiration Date	Indefinite
Canada Net Operating Loss Carryforwards [Member]
Operating Loss And Tax Credit Carryforwards [Line Items]
Amount	$ 197.9
Expiration Date, beginning year	2024
Expiration Date, ending year	2035
Canada [Member]
Operating Loss And Tax Credit Carryforwards [Line Items]
Amount	$ 278.0
Expiration Date	Indefinite
U S Federal [Member]
Operating Loss And Tax Credit Carryforwards [Line Items]
Amount	$ 198.4
Expiration Date	2034
State Net Operating Loss Carryforwards [Member]
Operating Loss And Tax Credit Carryforwards [Line Items]
Amount	$ 326.9
Expiration Date, beginning year	2016
Expiration Date, ending year	2034
United States [Member]
Operating Loss And Tax Credit Carryforwards [Line Items]
Amount	$ 59.4
Expiration Date	2018
U.S. Foreign Tax Credits [Member]
Operating Loss And Tax Credit Carryforwards [Line Items]
U.S. foreign tax credits	$ 33.9
Expiration Date, beginning year	2020
Expiration Date, ending year	2035
Foreign Tax Authority [Member]
Operating Loss And Tax Credit Carryforwards [Line Items]
Amount	$ 131.8
Amount	$ 34.7
Expiration Date	Indefinite
Expiration Date	Indefinite
Non-U.S. Net Operating Loss Carryforwards [Member]
Operating Loss And Tax Credit Carryforwards [Line Items]
Amount	$ 1.5
Expiration Date, beginning year	2016
Expiration Date, ending year	2034