Secured Debt Agreements, Net - Summary of Key Terms of Credit Facilities (Parenthetical) (Detail) - Credit Facilities [Member] - ExtensionOptions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
MetLife [Member]
Line of Credit Facility [Line Items]
Maturity period		Includes five one-year extension options which may be exercised at our sole discretion.
Number of extension options		5
Term of maturity date		1 year
Bank of America [Member]
Line of Credit Facility [Line Items]
Maturity period	Includes two one-year extension options which may be exercised at our sole discretion.
Number of extension options	2
Term of maturity date	1 year