The aggregate value of preferred stock dividends and other adjustments necessary to derive net income apportioned to common stockholders.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=117326831&loc=d3e1377-109256

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

Net Loss per Share Attributable to Common Stockholders - (Additional Information) (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended								12 Months Ended
	Jul. 31, 2018	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Subsidiary, Sale of Stock [Line Items]
Payments of a deemed dividend to the investor		$ (2,454)	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ (2,454)	$ 0	$ 0
IPO
Subsidiary, Sale of Stock [Line Items]
Shares sold in offering (in shares)	20,700,000