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Stockholders' Equity - Narrative (Details) - USD ($) |  |  |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Apr. 03, 2017 | May 09, 2016 | Jan. 01, 2015 | Dec. 31, 2017 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |
Treasury stock (in shares) |  |  |  | 0 | 0 | 0 |
Shares withheld for tax purposes and retired (in shares) |  |  |  |  | 65,952 | 18,229 |
Period for recognition |  |  |  |  | 3 years 4 months 24 days |  |
Total compensation cost attributable to shares awarded |  |  |  | $ 1,800,000 | $ 2,800,000 |  | $ 1,200,000
Nonvested awards, compensation costs not yet recognized |  |  |  | $ 1,600,000 | $ 1,600,000 |  |
Shares issued in acquisition of business (in shares) |  |  |  |  | 1,882,058 |  |
Share consideration given for Tealstone acquisition (1,882,058 shares) |  |  |  |  | $ 17,061,000 | $ 0 | 0
Net proceeds from stock issued |  |  |  |  | $ 0 | $ 19,142,000 | $ 0
Restricted Stock |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |
Grants in the period (in shares) |  |  |  |  | 217,341 | 79,240 | 978,526
Grants in the period (USD per share) |  |  |  |  | $ 10.69 | $ 4.36 | $ 4.53
Total compensation cost attributable to shares awarded |  |  |  |  | $ 353,000 | $ 250,000 | $ 250,000
Vested (in shares) |  |  |  |  | 612,463 | 351,855 | 166,622
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) |  |  |  |  | 180,542 | 20,000 | 917,851
Grants in the period (USD per share) |  |  |  |  | $ 10.92 | $ 4.78 | $ 4.55
Plan 2001 |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |
Weighted average remaining contractual term |  |  |  |  | 10 years |  |
Number of shares authorized for grant (in shares) |  |  |  | 1,900,000 | 1,900,000 |  |
Number of shares available for grant (in shares) |  |  |  | 400,289 | 400,289 |  |
Long-term Incentive Plan |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |
Percentage of incentive plan based on service completion |  |  | 50.00% |  |  |  |
Requisite service period |  |  | 3 years |  |  |  |
Percentage of incentive plan based on shareholder return |  |  | 50.00% |  |  |  |
Incentive plan term for shareholder return |  |  | 3 years |  |  |  |
Shares issued during the period, net of forfeitures (in shares) |  |  |  |  |  | 86,483 |
Total compensation cost attributable to shares awarded |  |  |  |  |  | $ 1,200,000 |
Vested (in shares) |  |  |  |  | 47,947 |  |
Forfeited in the period (in shares) |  |  |  |  | 0 | 29,781 | 24,738
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] |  |  |  |  |  |  |
Stock issued in equity offering, net of expense (in shares) |  | 5,175,000 |  |  |  |  |
Share price (USD per share) |  | $ 4 |  |  |  |  |
Share price, net (USD per share) |  | $ 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 |  |  |  |  |  |
Share consideration given for Tealstone acquisition (1,882,058 shares) | $ 17,061,000 |  |  |  |  |  |
Warrants to the Lenders Under the Loan Agreement |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |
Share price (USD per share) | $ 8.88 |  |  |  |  |  |
Warrants value | $ 3,500,000 |  |  | $ 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 shars) | 1,000,000 |  |  |  |  |  |
Warrant exercise price (USD per share) | $ 10.25 |  |  |  |  |  |

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