Investments - Summary of Investments (Detail) - USD ($)	Dec. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 10,884,460	$ 10,734,312
Available-for-sale Securities, Gross Unrealized Loss Gains	2,491	15,261
Available-for-sale Securities, Gross Unrealized Losses	(63,262)	(46,447)
Fair Value	10,823,689	10,703,126
Short-term investments (money market funds and accrued income) [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,269,178	94,595
Available-for-sale Securities, Gross Unrealized Loss Gains	0	0
Available-for-sale Securities, Gross Unrealized Losses	0	0
Fair Value	1,269,178	94,595
Obligations of U.S. Treasury, U.S. government corporations and agencies [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,561,937	2,017,250
Available-for-sale Securities, Gross Unrealized Loss Gains	887	3,885
Available-for-sale Securities, Gross Unrealized Losses	(5,616)	(349)
Fair Value	1,557,208	2,020,786
Mortgage-backed securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	53,755	66,982
Available-for-sale Securities, Gross Unrealized Loss Gains	1,345	2,550
Available-for-sale Securities, Gross Unrealized Losses	0	0
Fair Value	55,100	69,532
Certificates of deposit [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,000,000	2,000,000
Available-for-sale Securities, Gross Unrealized Loss Gains	225	0
Available-for-sale Securities, Gross Unrealized Losses	(7,033)	(24,755)
Fair Value	1,993,192	1,975,245
Corporate debt securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	5,999,590	6,555,485
Available-for-sale Securities, Gross Unrealized Loss Gains	34	8,826
Available-for-sale Securities, Gross Unrealized Losses	(50,613)	(21,343)
Fair Value	$ 5,949,011	$ 6,542,968

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
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