Stock-Based Compensation - Narrative (Details) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended				6 Months Ended		66 Months Ended
	Jul. 31, 2020 USD ($) shares	Jun. 30, 2020 USD ($) $ / shares shares	Mar. 31, 2020 USD ($) shares	Jun. 30, 2019 USD ($) $ / shares shares	Mar. 31, 2019 USD ($) shares	Jun. 30, 2020 USD ($) $ / shares shares	Jun. 30, 2019 USD ($) $ / shares shares	Jun. 30, 2020 shares	Apr. 29, 2020 shares	Apr. 28, 2020
Stock-Based Compensation
Shares issued under the Employee Stock Purchase Plan (in shares) | $		$ 257	$ 224	$ 211	$ 218
Employee stock
Stock-Based Compensation
Common stock available for issuance (in shares)		1,000,000				1,000,000		1,000,000
Common stock granted since inception (in shares)								672,907
Employee stock | Subsequent event
Stock-Based Compensation
Shares purchased during period (in shares)	44,137
Shares issued under the Employee Stock Purchase Plan (in shares) | $	$ 300
Service-based stock options
Stock-Based Compensation
Expiration period						10 years
Vesting period						4 years
Granted (in shares)		110,750		152,500		1,296,890	1,638,510
Weighted average grant-date fair value (in dollars per share) | $ / shares		$ 8.82		$ 11.94		$ 8.66	$ 12.74
Service-based stock options | Nonemployee directors
Stock-Based Compensation
Expiration period						10 years
Vesting period						1 year
Restricted Stock Units (RSUs)
Stock-Based Compensation
Vesting period						4 years
Restricted stock units granted (shares)		10,700		10,500		196,836	186,922
Weighted-average grant date fair value (in usd per share) | $ / shares		$ 14.49		$ 16.62		$ 11.41	$ 17.71
Grant-date fair value of restricted stock units granted | $		$ 200		$ 200		$ 2,200	$ 3,300
Shares vested in period (shares)		10,500	36,212
Restricted stock withheld for employee tax remittance (in shares)		0	13,872
Restricted Stock Units (RSUs) | Nonemployee directors
Stock-Based Compensation
Vesting period						1 year
Common Stock
Stock-Based Compensation
Shares purchased during period (in shares)		32,000	20,000	14,000	19,000
Shares issued under the Employee Stock Purchase Plan (in shares) | $		$ 257	$ 224	$ 211	$ 218
Restricted stock withheld for employee tax remittance (in shares)			14,000
Prior Plans
Stock-Based Compensation
Awards available for future grant under the Plan (in shares)		0				0		0
Omnibus Incentive Plan 2019
Stock-Based Compensation
Awards available for future grant under the Plan (in shares)		4,267,255				4,267,255		4,267,255
Ratio of full value awards against share reserve									1.4	1.25
Omnibus Incentive Plan 2019 | Common Stock
Stock-Based Compensation
Increase in number of shares available for issuance (shares)									2,400,000