Term Loan (Tables)

12 Months Ended

Dec. 31, 2018

Debt Disclosure [Abstract]

Schedule of Estimated Future Principal Payments Due Under Loan Agreement

Scheduled payments due under the Loan Agreement, excluding the final payment fee of $0.3 million and interest payments, are as follows:

	December 31, 2018
	(in thousands)
2020	$	1,667
2021		2,000
2022		1,333
Total	$	5,000