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Stock Incentive Plan and Other Equity Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Sep. 30, 2019 | Sep. 30, 2018
Sale of Stock [Line Items] |  |  |  |  |  |  |  |
Shares granted (in shares) |  |  |  |  |  |  | 375 |
Shares issued (in shares) |  |  |  |  |  |  | 192 |
Stock-based compensation expense | $ 819 |  |  | $ 798 |  |  | $ 2,489 | $ 2,181
Purchase of treasury stock |  |  | $ 3,201 |  |  |  |  |
Shares withheld for taxes | $ 32 | $ 98 | $ 564 | $ 7 | $ 107 | $ 194 |  |
Common Stock |  |  |  |  |  |  |  |
Sale of Stock [Line Items] |  |  |  |  |  |  |  |
Purchase of treasury stock (in shares) |  |  |  |  |  |  | 250 |
Purchase of treasury stock |  |  |  |  |  |  | $ 3,201 |
Shares withheld for taxes (in shares) | 3 |  |  |  |  |  | 62 |
Shares withheld for taxes | $ 32 |  |  |  |  |  | $ 694 |
ESPP |  |  |  |  |  |  |  |
Sale of Stock [Line Items] |  |  |  |  |  |  |  |
Maximum annual contributions per employee (percent) |  |  |  |  |  |  | 15.00% |
Maximum annual amount of contributions per employee |  |  |  |  |  |  | $ 25 |
Discount from market price on purchase date (percent) |  |  |  |  |  |  | 85.00% |
RSAs |  |  |  |  |  |  |  |
Sale of Stock [Line Items] |  |  |  |  |  |  |  |
Shares granted (in shares) |  |  |  |  |  |  | 52 |
Weighted Average Grant-Date Fair Value per Share (in dollars per share) |  |  |  |  |  |  | $ 12.06 |
Shares issued (in shares) |  |  |  |  |  |  | 52 |
RSUs |  |  |  |  |  |  |  |
Sale of Stock [Line Items] |  |  |  |  |  |  |  |
Shares granted (in shares) |  |  |  |  |  |  | 138 |
Weighted Average Grant-Date Fair Value per Share (in dollars per share) |  |  |  |  |  |  | $ 10.96 |
Shares issued (in shares) |  |  |  |  |  |  | 80 |
PSUs |  |  |  |  |  |  |  |
Sale of Stock [Line Items] |  |  |  |  |  |  |  |
Shares granted (in shares) |  |  |  |  |  |  | 185 |
Weighted Average Grant-Date Fair Value per Share (in dollars per share) |  |  |  |  |  |  | $ 10.89 |
Shares issued (in shares) |  |  |  |  |  |  | 54 |
ESPP |  |  |  |  |  |  |  |
Sale of Stock [Line Items] |  |  |  |  |  |  |  |
Shares issued (in shares) |  |  |  |  |  |  | 6 |
Stock-based compensation expense | $ 12 |  |  |  |  |  | $ 12 |
Remaining authorized shares available for purchase (in shares) | 794 |  |  |  |  |  | 794 |

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