Restructuring (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 4,900,000	$ 4,000,000
Reversal of non-cash-stock-based compensation expense	900,000	3,700,000
Payments for restructuring	900,000
Restructuring costs	5,800,000
Research and development [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	4,400,000	1,600,000
Selling, General and Administrative Expenses [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges		2,400,000
Employee Severance
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0	$ 7,700,000
Accrued Payroll
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 4,900,000