Selected Quarterly Financial Data (Details) - USD ($) $ / shares in Units, shares in Thousands	3 Months Ended								7 Months Ended	12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Dec. 31, 2016	Dec. 31, 2015
Selected Quarterly Financial Data [Abstract]
Revenue
Operating expenses:
General and administrative	$ 870,000	$ 893,000	$ 642,000	$ 528,000	$ 417,000	$ 408,000	$ 243,000	$ 156,000	43,000	2,933,000	1,224,000
Research and development	1,806,000	1,739,000	1,453,000	990,000	951,000	659,000	547,000	421,000	26,000	5,988,000	2,578,000
Amortization of intangible assets	167,000	166,000	166,000	166,000	167,000	167,000	166,000	166,000	111,000	665,000	666,000
Costs of business acquisitions									120,000
Total operating expenses	2,843,000	2,798,000	2,261,000	1,684,000	1,535,000	1,234,000	956,000	743,000	300,000	9,586,000	4,468,000
Other income:
Interest income	34,000	31,000	3,000							68,000
Total other income	34,000	31,000	3,000							68,000
Loss from operations, before income taxes	(2,809,000)	(2,767,000)	(2,258,000)	(1,684,000)	(1,535,000)	(1,234,000)	(956,000)	(743,000)	(300,000)	(9,518,000)	(4,468,000)
Income tax benefit					(518,000)	(483,000)	(357,000)	(299,000)	(23,000)		(1,657,000)
Net loss	(2,809,000)	(2,767,000)	(2,258,000)	(1,684,000)	(1,017,000)	(751,000)	(599,000)	(444,000)	(277,000)	(9,518,000)	(2,811,000)
Other comprehensive loss:
Unrealized gain (loss) on available-for-sale securities, net of tax	1,000	(8,000)								(7,000)
Comprehensive loss	$ (2,808,000)	$ (2,775,000)	$ (2,258,000)	$ (1,684,000)	$ (1,017,000)	$ (751,000)	$ (599,000)	$ (444,000)	$ (277,000)	$ (9,525,000)	$ (2,811,000)
Net loss per common share - basic and diluted	$ (0.21)	$ (0.21)	$ (0.23)	$ (0.22)	$ (0.13)	$ (0.10)	$ (0.08)	$ (0.06)	$ (0.11)	$ (0.86)	$ (0.37)
Weighted average shares used to compute net loss per common share	13,315	13,315	9,791	7,565	7,565	7,565	7,565	7,565	2,511	11,009	7,565