Organization and Summary of Accounting Policies - CARES ACT (Details) - USD ($)	3 Months Ended		6 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Jun. 30, 2020	Sep. 30, 2020	Sep. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Proceeds from grants received	$ 5,000,000			$ 53,000,000
Grant funds	(9,900,000)	$ 0	$ 43,100,000	33,200,000	$ 0
Accelerated payments	0			120,000,000
Deferred accrued payroll and benefits	$ 7,300,000			$ 7,300,000