Summary of Significant Accounting Policies, Fair Value Measurements (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Level 2 [Member]
Fair Value of Financial Instruments [Abstract]
Assets, fair value	$ 0
Liabilities, fair value	0
Level 3 [Member]
Fair Value of Financial Instruments [Abstract]
Assets, fair value	0
Liabilities, fair value	$ 0
Warrant liability, fair value		$ 7,673