Derivative Financial Instruments - Summary of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - Free Standing Warrants [Member] - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2015
Derivative [Line Items]
Derivative liabilities	$ 100	$ 0
Level 1 [Member]
Derivative [Line Items]
Derivative liabilities		0
Level 2 [Member]
Derivative [Line Items]
Derivative liabilities	$ 100	0
Level 3 [Member]
Derivative [Line Items]
Derivative liabilities		$ 0