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Stockholders' Equity - Narrative (Details) |  |  | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Apr. 03, 2017 USD ($) $ / shares shares | May 09, 2016 USD ($) $ / shares shares | Dec. 31, 2018 USD ($) vote $ / shares shares | Dec. 31, 2017 USD ($) $ / shares shares | Dec. 31, 2016 USD ($) $ / shares shares | Nov. 02, 2018 USD ($) | May 31, 2018 shares
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |
Common stock, votes entitled per share | vote |  |  | 1 |  |  |  |
Preferred stock, shares issued (in shares) |  |  | 0 | 0 |  |  |
Repurchase of common stock (in shares) |  |  | 466,519 |  |  |  |
Treasury stock (in shares) |  |  | 466,519 | 0 |  |  |
Shares withheld for tax purposes and retired (in shares) |  |  | 28,291 | 65,952 |  |  |
Grants in the period (in shares) |  |  | 1,196,575 | 217,341 | 79,240 |  |
Grants in the period (USD per share) | $ / shares |  |  | $ 12.58 | $ 10.69 | $ 4.36 |  |
Period for recognition |  |  | 3 years 9 months 7 days |  |  |  |
Vested (in shares) |  |  | 150,280 | 612,463 | 351,855 |  |
Nonvested awards, compensation costs not yet recognized | $ |  |  | $ 13,600,000 |  |  |  |
Total compensation cost attributable to shares awarded | $ |  |  | 3,100,000 | $ 2,800,000 | $ 1,800,000 |  |
Shares issued in acquisition of business (in shares) |  |  |  | 1,882,058 |  |  |
Share consideration given for Tealstone acquisition (in shares) | $ |  |  | 0 | $ 17,061,000 | 0 |  |
Net proceeds from stock issued | $ |  |  | 0 | 0 | 19,142,000 |  |
Warrants issued to lenders | $ |  |  | 0 | 3,500,000 | 0 |  |
Restricted Stock |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |
Total compensation cost attributable to shares awarded | $ |  |  | $ 509,988 | $ 353,000 | $ 250,000 |  |
Restricted Stock | Minimum |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |
Period for recognition |  |  | 2 years |  |  |  |
Restricted Stock | Maximum |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |
Period for recognition |  |  | 4 years |  |  |  |
Restricted Stock | Key Employees |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |
Grants in the period (in shares) |  |  | 1,147,285 | 180,542 | 20,000 |  |
Grants in the period (USD per share) | $ / shares |  |  | $ 12.62 | $ 10.92 | $ 4.78 |  |
Restricted Stock | Non Employee Director |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |
Period for recognition |  |  | 1 year |  |  |  |
Total compensation cost attributable to shares awarded | $ |  |  | $ 63,745 |  |  |  |
Plan 2001 |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |
Number of shares authorized for grant (in shares) |  |  | 1,900,000 |  |  |  |
Plan 2018 |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |
Number of shares authorized for grant (in shares) |  |  |  |  |  |  | 1,800,000
Long-term Incentive Plan |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |
Vested (in shares) |  |  |  | 47,947 |  |  |
Forfeited in the period (in shares) |  |  | 0 |  | 29,781 |  |
Long-term Incentive Plan | Performance Shares |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |
Vested (in shares) |  |  |  | 15,982 |  |  |
D.A. Davidson and Co. |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |
Share price (USD per share) | $ / shares |  | $ 4 |  |  |  |  |
Share price, net (USD per share) | $ / shares |  | $ 3.77 |  |  |  |  |
Net proceeds from stock issued | $ |  | $ 19,100,000 |  |  |  |  |
Tealstone |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |
Shares issued in acquisition of business (in shares) | 1,882,058 |  |  | 1,882,058 |  |  |
Share consideration given for Tealstone acquisition (in shares) | $ | $ 17,061,000 |  |  |  |  |  |
Warrants to the Lenders Under the Loan Agreement |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |
Share price (USD per share) | $ / shares | $ 8.88 |  |  |  |  |  |
Warrants issued to lenders | $ | $ 3,500,000 |  |  | $ 3,500,000 |  |  |
Warrants to the Lenders Under the Loan Agreement | Loan and Security Agreement |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |
Warrants, term | 5 years |  |  |  |  |  |
Number of shares issued if warrants are called (in shares) | 1,000,000 |  |  |  |  |  |
Warrant exercise price (USD per share) | $ / shares | $ 10.25 |  |  |  |  |  |
Common Stock |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |
Stock repurchase program, authorized amount | $ |  |  |  |  |  | $ 2,000,000 |
Stock issued in equity offering, net of expense (in shares) |  | 5,175,000 |  |  | 5,175,000 |  |
Common Stock | Plan 2018 |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |
Number of shares available for grant (in shares) |  |  | 957,392 |  |  |  |

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