Commitments and Contingencies - Information Related to Operating Lease (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Commitments And Contingencies Disclosure [Abstract]
Operating lease expense (including variable costs of $88 and $82 during the three months ended March 31, 2021 and 2020)	$ 285	$ 279
Cash paid for amounts included in the measurement of lease liabilities	$ 209	$ 180

Amount of operating lease expense. Excludes sublease income.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918638-209977

Name:	us-gaap_OperatingLeaseExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration