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Stock-based Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Apr. 14, 2020	Jul. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized (in shares)						7,150,000
Stock-based compensation expense	$ 1.0	$ 0.6	$ 1.8	$ 1.2
Share-based compensation, nonvested awards, compensation cost not yet recognized	$ 5.7		$ 5.7
Period for recognition of compensation on unvested stock option (in years)			2 years 1 month 6 days
Grant date fair value of performance-based restricted stock units (in dollars per share)					$ 1.70
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized (in shares)		500,000		500,000
Shares issued (in shares)			253,042