Commitments and Contingencies - Agreements with Executive Officers and Key Employees (Details)	12 Months Ended
	Dec. 31, 2019 USD ($)
Kasbar agreement
Loss contingencies
Annual base salary	$ 900,000
Agreement expiration term, extension under specified condition	1 year
Minimum period prior to expiration of the term for serving specified notice to prevent extension of the agreement term	1 year
Severance payment for termination following a change of control	$ 5,000,000.0
Severance payment for termination following other scenarios	$ 3,000,000.0
Vesting period of outstanding equity awards	2 years
Period for severance payment after termination of executive's employment	2 years
Agreements with executive officers and key employees
Future minimum commitments under agreements with executive officers and key employees
2019	$ 900,000