Summary of Significant Accounting Policies - Narrative (Details) - USD ($)	3 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Class of Stock [Line Items]
Operating expenses		$ 16,519,000	$ 83,327,000	$ 208,195,000
Fixed asset impairment		0	0
Operating lease right-of-use assets		2,604,000	3,612,000
Present value of lease liabilities		2,314,000
Cumulative Effect, Period of Adoption, Adjustment
Class of Stock [Line Items]
Operating lease right-of-use assets	$ 5,046,000			5,046,000
Present value of lease liabilities	5,131,000			5,131,000
Developed Technology | Noctiva
Class of Stock [Line Items]
Fixed asset impairment	$ 66,087,000
Advertising
Class of Stock [Line Items]
Operating expenses		$ 312,000	$ 372,000	$ 17,562,000