Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2011
Income Tax Disclosure [Abstract]
Provision for income taxes	$ 0	$ 0
Increase in valuation allowance	500,000	700,000
Valuation allowance for operating loss and tax credit carryforwards	0	0
Capital loss carryforwards		$ 300,000
Capital loss carryforwards expiration period		2014
Net operating loss carryforwards	$ 81,000,000
Capital loss carryforwards expiration period start	2018
Capital loss carryforwards expiration period end	2035
Period for suspension of net operating loss carryforwards			4 years
Extension of the term of net loss carryforwards			4 years