Basis of Presentation and Summary of Significant Accounting Policies - Additional Information (Details)		6 Months Ended
	Nov. 26, 2018	Jun. 30, 2019 USD ($)	Jan. 01, 2019 USD ($)
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Reverse stock split description		1-for-1.60224 reverse stock split of its common stock
Reverse stock split ratio	0.62
Realized gains (losses) on sale or maturity of marketable securities		$ 0
Impairment on available- for- sale of equity securities		0
Operating lease right-of-use asset		$ 3,003,000
ASU 2016-02
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Operating lease, liabilities			$ 3,300,000
Operating lease right-of-use asset			$ 3,200,000