Summary of Significant Accounting Policies - Estimated Fair Values of Financial Instrument Assets and Liabilities Which are Not Measured at Fair Value on the Consolidated Balance Sheets (Parenthetical) (Detail) - Fair Value, Measurements, Nonrecurring [Member] $ in Thousands	Dec. 31, 2015 USD ($)
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Other investments, at cost	$ 1,539
Accounts payable, accrued expenses and other liabilities	$ 1,267