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Stock Incentive Plan - Narrative (Details) - USD ($) |  | 12 Months Ended |
--- | --- | --- | ---
Apr. 03, 2017 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |
Value of shares withheld for taxes |  | $ 7,338,000 | $ 1,985,000 | $ 1,109,000 |
Warrants exercised (in shares) |  | 530,000 | 470,000 |  |
Stock issued during period (in shares) |  | 315,000 | 110,000 |  |
Stock issued related to warrants exercised |  | $ 8,082,000 | $ 1,477,000 | $ 0 |
Warrants outstanding (in shares) |  | 0 |  |  |
RSAs |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |
Total compensation cost attributable to shares awarded |  | $ 646,000 |  |  |
Share vesting period |  | 3 years |  |  |
Grants in the period (in shares) |  | 29,000 | 51,000 | 52,000 |
Grants in the period (USD per share) |  | $ 23.19 | $ 8.73 | $ 12.06 |
Fair value of shares vested in period |  | $ 506,000 | $ 799,000 | $ 1,261,000 |
Vested (in shares) |  | 55,000 |  |  |
Vested (in usd per share) |  | $ 9.26 |  |  |
Shares withheld for taxes (in shares) |  | 1,000 | 11,000 | 17,000 |
Value of shares withheld for taxes |  | $ 27,000 | $ 140,000 | $ 255,000 |
RSUs |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |
Total compensation cost attributable to shares awarded |  | $ 2,128,000 |  |  |
Share vesting period |  | 3 years |  |  |
Grants in the period (in shares) |  | 151,000 | 169,000 | 261,000 |
Grants in the period (USD per share) |  | $ 21.29 | $ 13.52 | $ 12.14 |
Fair value of shares vested in period |  | $ 2,742,000 | $ 2,918,000 | $ 1,709,000 |
Vested (in shares) |  | 182,000 |  |  |
Vested (in usd per share) |  | $ 15.05 |  |  |
PSUs |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |
Total compensation cost attributable to shares awarded |  | $ 8,913,000 |  |  |
Share vesting period |  | 3 years |  |  |
Grants in the period (in shares) |  | 397,000 | 176,000 | 310,000 |
Grants in the period (USD per share) |  | $ 21.88 | $ 14.06 | $ 11.81 |
Fair value of shares vested in period |  | $ 7,842,000 | $ 1,620,000 | $ 948,000 |
Vested (in shares) |  | 658,000 |  |  |
Vested (in usd per share) |  | $ 11.91 |  |  |
RSUs and PSUs |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |
Shares withheld for taxes (in shares) |  | 311,000 | 123,000 | 74,000 |
Value of shares withheld for taxes |  | $ 7,311,000 | $ 1,845,000 | $ 964,000 |
Warrants to the Lenders Under the Loan Agreement | Loan and Security Agreement |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |
Warrants, term | 5 years |  |  |  |
Number of warrants (in shares) | 1,000,000 |  |  |  |
Warrant exercise price (USD per share) | $ 10.25 |  |  |  |
Stock Incentive Plan & ESPP |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |
Total compensation cost attributable to shares awarded |  | $ 11,771,000 | 11,643,000 | 3,788,000 |
Stock Incentive Plan |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |
Number of shares authorized to issue (in shares) |  |  |  |  | 3,400,000
Number of shares available for grant (in shares) |  | 882,000 |  |  |
Unrecognized compensation cost |  | $ 6,300,000 |  |  |
Weighted-average recognition period |  | 1 year 2 months 12 days |  |  |
Stock Incentive Plan | RSAs, RSUs and PSUs |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |
Total compensation cost attributable to shares awarded |  | $ 11,687,000 | 11,572,000 | 3,761,000 |
ESPP |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |
Number of shares available for grant (in shares) |  | 725,000 |  |  |
ESPP | Employee Stock |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |
Total compensation cost attributable to shares awarded |  | $ 84,000 | $ 71,000 | $ 27,000 |
Maximum annual contribution per employee |  | 15.00% |  |  |
Maximum annual contribution amount |  | $ 25,000 |  |  |
Purchase price of common stock percent |  | 85.00% |  |  |

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