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STOCKHOLDERS' EQUITY - Narrative (Detail) | 8 Months Ended | 12 Months Ended |
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Dec. 31, 2014 USD ($) $ / shares | Dec. 31, 2016 USD ($) Vote $ / shares shares | Dec. 31, 2015 USD ($) Vote $ / shares shares | Apr. 30, 2014 USD ($) $ / shares | Apr. 30, 2007 shares
Limited Partners' Capital Account [Line Items] |  |  |  |  |
Preferred stock authorized to issue (up to) (in shares) | shares |  | 944,000 |  |  |
Shares issued (in shares) | shares |  | 0 | 0 |  |
Options granted (in USD per share) | $ / shares | $ 3.62 | $ 0 | $ 5.35 | $ 4.22 |
Granted (in USD per share) | $ / shares |  | $ 8.97 |  |  |
Expected dividend yield |  | 0.00% |  |  |
Expected life | 7 years | 1 day | 7 years 2 months 27 days | 6 years 9 months 18 days |
Risk-free interest rate | 2.15% | 0.00% | 2.02% | 2.22% |
Expected volatility | 82.76% | 0.00% | 81.31% | 83.96% |
Total fair value of other stock awards vested | $ 1,866,000 | $ 3,238,000 | $ 2,340,000 | $ 1,458,000 |
Tax benefits from additional paid-in-capital adjustments | 84,000 | $ 0 | 185,000 | 0 |
Market-based Performance Stock Options |  |  |  |  |
Limited Partners' Capital Account [Line Items] |  |  |  |  |
Expected dividend yield |  | 0.00% |  |  |
Weighted average fair value of market-based performance (in USD per share) | $ / shares |  | $ 6.70 |  |  |
Expected life |  | 7 years 4 months 24 days |  |  |
Risk-free interest rate |  | 2.15% |  |  |
Expected volatility |  | 43.10% |  |  |
Stock Options |  |  |  |  |
Limited Partners' Capital Account [Line Items] |  |  |  |  |
Stock-based compensation expense | 386,000 | $ 605,000 | 671,000 | 464,000 |
Aggregate intrinsic value of stock options exercised | 31,000 | 22,000 | 52,000 | 23,000 |
Total unrecognized stock-based compensation expense related to all outstanding stock options (in shares) |  | $ 1,218,000 |  |  |
Unrecognized stock-based compensation expense, weighted average period |  | 1 year 6 months |  |  |
Restricted Stock, Restricted Stock Units and Performance Stock Units |  |  |  |  |
Limited Partners' Capital Account [Line Items] |  |  |  |  |
Stock-based compensation expense | $ 1,202,000 | $ 2,673,000 | $ 2,314,000 | $ 1,861,000 |
Granted (in USD per share) | $ / shares | $ 4.90 | $ 8.97 | $ 4.40 | $ 4.28 |
Income taxes associated with stock-based compensation expense | $ 0 | $ 0 | $ 19,000 | $ 0 |
Restricted Stock and Restricted Stock Unit |  |  |  |  |
Limited Partners' Capital Account [Line Items] |  |  |  |  |
Unrecognized stock-based compensation expense |  | $ 3,212,000 |  |  |
Unrecognized stock-based compensation expense, weighted average period |  | 1 year 8 months 12 days |  |  |
Incremental compensation expense |  |  | 270,000 |  |
Performance Shares |  |  |  |  |
Limited Partners' Capital Account [Line Items] |  |  |  |  |
Unrecognized stock-based compensation expense |  | $ 4,037,000 |  |  |
Unrecognized stock-based compensation expense, weighted average period |  | 2 years |  |  |
Market-based Performance Stock Units |  |  |  |  |
Limited Partners' Capital Account [Line Items] |  |  |  |  |
Expected dividend yield |  | 0.00% |  |  |
Weighted average fair value of market-based performance (in USD per share) | $ / shares |  | $ 14.30 |  |  |
Risk-free interest rate |  | 1.07% |  |  |
Expected volatility |  | 33.00% |  |  |
Amended and Restated 1997 Employee Stock Purchase Plan |  |  |  |  |
Limited Partners' Capital Account [Line Items] |  |  |  |  |
Stock-based compensation expense | $ 52,000 | $ 115,000 | $ 94,000 | $ 79,000 |
2016 Incentive Plan |  |  |  |  |
Limited Partners' Capital Account [Line Items] |  |  |  |  |
Options granted period |  | 10 years |  |  |
Non-Employee Director | Restricted Stock Awards |  |  |  |  |
Limited Partners' Capital Account [Line Items] |  |  |  |  |
Options vesting period |  | 3 years |  |  |
Minimum | 2016 Incentive Plan |  |  |  |  |
Limited Partners' Capital Account [Line Items] |  |  |  |  |
Options vesting period |  | 1 year |  |  |
Maximum | 2016 Incentive Plan |  |  |  |  |
Limited Partners' Capital Account [Line Items] |  |  |  |  |
Options vesting period |  | 4 years |  |  |
Class A Common Stock |  |  |  |  |
Limited Partners' Capital Account [Line Items] |  |  |  |  |
Vote for each share held (in votes per share) | Vote |  | 1 |  |  |
Number of shares available for future grant (in shares) | shares |  | 184,000 |  |  |
Class A Common Stock | 2016 Incentive Plan |  |  |  |  |
Limited Partners' Capital Account [Line Items] |  |  |  |  |
Common stock, authorized shares (in shares) | shares |  |  |  |  | 2,250,000
Number of shares available for future grant (in shares) | shares |  | 2,489,000 |  |  |
Class B Common Stock |  |  |  |  |
Limited Partners' Capital Account [Line Items] |  |  |  |  |
Vote for each share held (in votes per share) | Vote |  | 10 | 10 |  |

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- Definition The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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