Income Taxes - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands			5 Months Ended	8 Months Ended		9 Months Ended	12 Months Ended
	Dec. 16, 2019	Apr. 17, 2019	Sep. 30, 2019	Dec. 31, 2019	Dec. 30, 2019	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jul. 31, 2018
Operating Loss Carryforwards [Line Items]
Net deferred tax liability resulting from corporate reorganization				$ 198			$ 198	$ 3,684		$ 3,100
Deferred tax asset arising from the IPO			$ 13,700	13,664
Effective income tax rate (as a percent)							11.00%
Total income tax provision							$ 2,679	$ 327	$ 1,008
Federal statutory tax rate (as a percent)						21.00%
Deferred tax assets				18,800			$ 18,800
December Offering
Operating Loss Carryforwards [Line Items]
Deferred tax asset arising from the IPO				$ 9,508
Deferred tax asset arising from issuance of common stock in the December 2019 Offering					$ 9,500
Class A Common Stock
Operating Loss Carryforwards [Line Items]
Share price (in dollars per share)		$ 18.00
Class A Common Stock | Initial Public Offering
Operating Loss Carryforwards [Line Items]
Sale of stock, number of shares issued (in shares)		16,675,000
Share price (in dollars per share)		$ 18.00
Class A Common Stock | December Offering
Operating Loss Carryforwards [Line Items]
Sale of stock, number of shares issued (in shares)	12,650,000
Class A Common Stock | December Offering, Company
Operating Loss Carryforwards [Line Items]
Sale of stock, number of shares issued (in shares)	6,000,000
Class A Common Stock | December Offering, Selling Shareholders
Operating Loss Carryforwards [Line Items]
Sale of stock, number of shares issued (in shares)	6,650,000
Share price (in dollars per share)	$ 18.10
Class A Common Stock | December Offering, Equivalent Units Issued
Operating Loss Carryforwards [Line Items]
Sale of stock, number of shares issued (in shares)	5,496,813