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Stockholders' Equity - Narrative (Details)		3 Months Ended		13 Months Ended
Stockholders' Equity - Narrative (Details)	Nov. 06, 2018 $ / shares shares	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($)	Dec. 31, 2020 USD ($) $ / shares shares	Sep. 30, 2020 $ / shares shares	Jan. 31, 2020 shares	Dec. 13, 2019 USD ($)	Feb. 28, 2019	Oct. 23, 2018 $ / right $ / shares shares	Mar. 07, 2018 shares	Mar. 10, 2017 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense \| $		$ 25,000,000.0		$ 25,000,000.0
Weighted average period for unrecognized compensation expense expected to be recognized (in years)		2 years 8 months 12 days
Purchase of common stock (in shares)		921,015		921,015	1,162,505
Discount rate from market price, purchase date		0.15
Recognized compensation expense \| $		$ 2,747,000	$ 2,303,000
Total intrinsic value of options exercised \| $		$ 1,500,000	100,000
Amount authorized and approved under share repurchase program \| $							$ 10,000,000
Amount of shares repurchased \| $				$ 1,000,000.0
Number of shares repurchased (in shares)				137,000
Average price of shares repurchased (in dollars per share) \| $ / shares				$ 7.33
Preferred stock, par value (in dollars per share) \| $ / shares		$ 0.001		$ 0.001	$ 0.001
Percentage of common stock outstanding for acquiring person under right agreement								4.90%
Series B Preferred Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of preferred share purchase right for each share of common stock (in shares)									1
Preferred stock, share conversion ratio									0.001000
Preferred stock, par value (in dollars per share) \| $ / shares									$ 0.001
Preferred stock, purchase price per right (in dollars per right) \| $ / right									35.00
Preferred stock, redemption price per share (in dollars per share) \| $ / shares									$ 0.0001
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period for unrecognized compensation expense expected to be recognized (in years)		2 years 9 months 18 days
Awards outstanding (in shares)		2,627,825		2,627,825	2,661,943
Recognized compensation expense \| $		$ 1,900,000	1,700,000
Unrecognized compensation expense related to nonvested awards \| $		19,200,000		$ 19,200,000
Performance RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense \| $		$ 3,600,000		$ 3,600,000
Weighted average period for unrecognized compensation expense expected to be recognized (in years)		2 years 9 months 18 days
Awards outstanding (in shares)		638,321		638,321	353,556
Recognized compensation expense \| $		$ 300,000	200,000
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period for unrecognized compensation expense expected to be recognized (in years)		2 years 3 months 18 days
Recognized compensation expense \| $		$ 200,000	200,000
Unrecognized compensation expense related to outstanding stock options \| $		1,400,000		$ 1,400,000
Performance options \| Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense \| $		$ 700,000		$ 700,000
Weighted average period for unrecognized compensation expense expected to be recognized (in years)		9 months 18 days
Number of common stock reserved for future grants (in shares)	800,000
Recognized compensation expense \| $		$ 200,000	200,000
Exercise price per share (in dollars per share) \| $ / shares	$ 9.50
Vesting period of awards	3 years
2020 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance (in shares)						4,500,000
Number of common stock reserved for future grants (in shares)		2,719,465		2,719,465
2020 Plan \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards outstanding (in shares)		975,746		975,746
2020 Plan \| Performance RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards outstanding (in shares)		638,321		638,321
Prior Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance (in shares)						107,903
Purchase of common stock (in shares)		611,226		611,226
Prior Plans \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards outstanding (in shares)		1,264,921		1,264,921
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance (in shares)		649,326		649,326						1,000,000
Shares issued to participants pursuant to employee stock purchase plan (in shares)		350,674
Recognized compensation expense \| $		$ 100,000	$ 100,000
ESPP \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Discount rate from market price, offering date		15.00%
Director Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance (in shares)											1,500,000
Number of common stock reserved for future grants (in shares)		267,533		267,533
Director Plan \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase of common stock (in shares)		327,946		327,946