Derivative Financial Instruments - Schedule of Derivative Liabilities Measured at Fair Value Using Observable Inputs (Level 2) (Detail) - Level 2 [Member] - Warranty Liability [Member] $ in Millions	9 Months Ended
	Sep. 30, 2016 USD ($) shares
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Increase due to issuance of warrants | $	$ 136
Decrease due to fair value of warrants | $	(36)
Warrant liability, Ending Balance | $	$ 100
Number of warrants shares, Increase due to issuance of warrants | shares	84,986
Number of warrants shares, Decrease due to fair value of warrants | shares	0
Number of warrants liability shares, Ending Balance | shares	84,986