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Stock Based Compensation - Additional Information (Details) - USD ($) $ in Thousands				3 Months Ended		9 Months Ended
	Jan. 01, 2021	Jan. 01, 2018	Nov. 09, 2017	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares)				3,601,238		3,601,238		2,725,956
Estimated grant date fair value of options vested				$ 153	$ 193	$ 199	$ 322
Unrecognized cost for stock based compensation				$ 5		$ 5
Stock options issued and outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options, granted (in shares)				0	0	0	0
Unrecognized cost for stock based compensation, period for recognition (in years)						1 month 2 days
Restricted stock units issued and outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares)				369,614		369,614		450,614
Unrecognized cost for stock based compensation, period for recognition (in years)						2 years 10 months 9 days
Unrecognized compensation cost related to non-vested RSUs				$ 25,509		$ 25,509
2010 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant (in shares)				0		0
2017 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares)			1,050,000
Common stock reserved for future issuance, percent increase		5.00%
Increase in shares available for grant (in shares)	1,120,650
2017 Plan \| Stock options issued and outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)			4 years
Contractual life (in years)			10 years
2017 Plan \| Restricted stock units issued and outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period			4 years
2017 Plan \| Restricted stock units issued and outstanding \| Non-employee Board of Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			25.00%
2017 Plan \| Restricted stock units issued and outstanding \| Executives
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)			4 years
2017 Plan \| Restricted stock units issued and outstanding \| Executives \| Year one vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			50.00%
2017 Plan \| Restricted stock units issued and outstanding \| Executives \| First quarter vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			12.50%
2017 Plan \| Restricted stock units issued and outstanding \| Executives \| Second quarter vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			12.50%
2017 Plan \| Restricted stock units issued and outstanding \| Executives \| Third quarter vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			12.50%
2017 Plan \| Restricted stock units issued and outstanding \| Executives \| First quarter vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			12.50%
2017 Plan \| Restricted stock units issued and outstanding \| Executives \| Year two, three and four vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			50.00%