v3.6.0.2
Provision for Income Taxes - Expiration of Tax Loss Carryforwards (Detail)
$ in Millions
Dec. 31, 2016
USD ($)
Operating Loss Carryforwards [Line Items]  
Tax loss carryforwards $ 1,899
2017 Tax Loss Carryforwards [Member]  
Operating Loss Carryforwards [Line Items]  
Tax loss carryforwards 26
2018 Tax Loss Carryforwards [Member]  
Operating Loss Carryforwards [Line Items]  
Tax loss carryforwards 10
2019 Tax Loss Carryforwards [Member]  
Operating Loss Carryforwards [Line Items]  
Tax loss carryforwards 29
2020 Tax Loss Carryforwards [Member]  
Operating Loss Carryforwards [Line Items]  
Tax loss carryforwards 10
2021 Tax Loss Carryforwards [Member]  
Operating Loss Carryforwards [Line Items]  
Tax loss carryforwards 1
2022-2026 Tax Loss Credit Carryforwards [Member]  
Operating Loss Carryforwards [Line Items]  
Tax loss carryforwards 947
Later Tax Loss Carryforwards [Member]  
Operating Loss Carryforwards [Line Items]  
Tax loss carryforwards 290
Unlimited Tax Credit Loss Carryforwards [Member]  
Operating Loss Carryforwards [Line Items]  
Tax loss carryforwards $ 586