Organization and Summary of Significant Accounting Policies - Income Taxes (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accounting Policies [Abstract]
Income tax expense (benefit)	$ 0	$ 0	$ 0
Net deferred tax assets	$ 14,300,000	$ 16,700,000