v3.8.0.1

SHAREHOLDER'S EQUITY (Details) - USD ($) | 1 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Dec. 15, 2017 | Nov. 17, 2017 | Sep. 15, 2017 | Aug. 30, 2017 | Jun. 15, 2017 | Mar. 15, 2017 | Dec. 15, 2016 | Sep. 15, 2016 | Jun. 15, 2016 | Dec. 31, 2017 | Oct. 16, 2017 | Sep. 30, 2017 | Jul. 16, 2017 | Jun. 30, 2017 | Apr. 16, 2017 | Mar. 31, 2017 | Jan. 16, 2017 | Dec. 31, 2016 | Oct. 16, 2016 | Sep. 30, 2016 | Jul. 16, 2016 | Jun. 30, 2016 | Apr. 16, 2016 | Mar. 31, 2016 | Jan. 16, 2016 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Conversion Of Class B Common Stock [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Conversion of Class B common stock to Class A common stock (Share) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3,152,333 |  |
Dividends And Shares Activitiy [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dvidend Equivalent liability - short term |  |  |  |  |  |  |  |  |  | $ 830,000 |  |  |  |  |  |  |  | $ 260,000 |  |  |  |  |  |  |  | $ 830,000 | $ 260,000 |
Dvidend Equivalent liability - long term |  |  |  |  |  |  |  |  |  | 1,331,000 |  |  |  |  |  |  |  | 348,000 |  |  |  |  |  |  |  | 1,331,000 | 348,000 |
Total Dividend Equivalent Liability |  |  |  |  |  |  |  |  |  | $ 2,161,000 |  |  |  |  |  |  |  | 608,000 |  |  |  |  |  |  |  | $ 2,161,000 | $ 608,000 |
CommonStockDividendsPerShareDeclared | $ 0.09 |  | $ 0.075 | $ 0.2 | $ 0.075 | $ 0.075 | $ 0.075 | $ 0.075 | $ 0.075 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.36 | $ 0.3 |
Dividend payments | $ 12,633,039 |  | $ 2,921,727 | $ 7,791,075 | $ 2,920,860 | $ 2,915,952 | $ 2,891,608 | $ 2,886,179 | $ 2,885,838 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 29,296,000 | $ 8,666,000 | $ 0
Shares of stock deemed repurchased |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 169,000 | 232,000 | 132,000
Amount recorded as financing activity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ (2,565,000) | $ (2,268,000) | $ (1,562,000)
The total cost to repurchase |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (10,675,000) | 0 | 0
Dividends paid on preferred stock |  | $ 236,806 |  |  |  |  |  |  |  |  | $ 687,500 |  | $ 550,000 |  | $ 550,000 |  | $ 550,000 |  | $ 550,000 |  | $ 412,500 |  | $ 412,500 |  | $ 412,500 | $ 2,574,000 | 1,788,000 | 752,000
Employee stock purchase plan, authorized shares |  |  |  |  |  |  |  |  |  | 1,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,000,000 |  |
Stock Issued During Period Value Employee Stock Purchase Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 182,000 | 379,000 | 0
Total Non cash compensation expense recognized |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 6,239,000 | 4,218,000 | 3,488,000
Espp Shares Market Value |  |  |  |  |  |  |  |  |  | 85.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 85.00% |  |
Espp Share Discount |  |  |  |  |  |  |  |  |  | 15.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 15.00% |  |
PreferredStockDividendsPerShareDeclared |  | $ 21,527.78 |  |  |  |  |  |  |  |  | $ 62,500 |  | $ 50,000 |  | $ 50,000 |  | $ 50,000 |  | $ 50,000 |  | $ 37,500 |  | $ 37,500 |  | $ 37,500 |  |  |
PaymentsOfDividendsAbstract |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments of Dividends, Common Stock | $ 12,633,039 |  | $ 2,921,727 | $ 7,791,075 | $ 2,920,860 | $ 2,915,952 | $ 2,891,608 | $ 2,886,179 | $ 2,885,838 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 29,296,000 | 8,666,000 | 0
PaymentsOfDividendsPreferredStockAndPreferenceStock |  |  |  |  |  |  |  |  |  | $ 924,000 |  | $ 550,000 |  | $ 550,000 |  | $ 550,000 |  | $ 550,000 |  | $ 413,000 |  | $ 413,000 |  | $ 412,000 |  | 2,574,000 | $ 1,788,000 | $ 413,000
Treasury Stock Line Items |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Repurchase Prgram Authorized Amount |  |  |  |  |  |  |  |  |  | $ 100,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 100,000,000 |  |
Shares repurchased during period |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 932,600 |  |
Average Cost per share of Acquired Treasury Shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 11.45 |  |
ESPP [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends And Shares Activitiy [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period Shares Employee Stock Purchase Plans |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 15,000 | 32,000 | 0
Total Non cash compensation expense recognized |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 32,000 | $ 67,000 | $ 0

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