Receivables Held for Investment, net - Additional Information on Nonaccrual Receivables (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Receivables [Abstract]
Interest income that would have been recorded if the nonaccrual receivable had been current in accordance with contractual terms during the period	$ 78	$ 163	$ 354
Interest income that was recorded on nonaccrual receivables during the period	$ 27	$ 59	$ 114