Principal Activity and Significant Accounting Policies - Schedule of Tax Status (Detail) - 10K - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Tax status
Ordinary income	$ 0.8671	$ 0.6649
Capital Gain	0.0098	0.0281
Return of capital	0.0531	0.2070
Total	$ 0.9300	$ 0.9000
Ordinary income	93.24%	73.88%
Capital Gain	1.05%	3.12%
Return of capital	5.71%	23.00%
Total	100.00%	100.00%