v3.10.0.1

SHAREHOLDER'S EQUITY (Details) - USD ($) |  | 1 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Mar. 28, 2018 | Dec. 14, 2018 | Sep. 14, 2018 | Jun. 28, 2018 | Dec. 15, 2017 | Nov. 17, 2017 | Sep. 15, 2017 | Aug. 30, 2017 | Jun. 15, 2017 | Mar. 15, 2017 | Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2017 | Oct. 16, 2017 | Sep. 30, 2017 | Jul. 16, 2017 | Jun. 30, 2017 | Apr. 16, 2017 | Mar. 31, 2017 | Jan. 16, 2017 | Oct. 16, 2016 | Jul. 16, 2016 | Apr. 16, 2016 | Jan. 16, 2016 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
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 |  |  |  |  |  |  |  |  |  |  | $ 1,279,000 |  |  |  | $ 830,000 |  |  |  |  |  |  |  |  |  |  |  | $ 1,279,000 | $ 830,000 |
Dvidend Equivalent liability - long term |  |  |  |  |  |  |  |  |  |  | 1,041,000 |  |  |  | 1,331,000 |  |  |  |  |  |  |  |  |  |  |  | 1,041,000 | 1,331,000 |
Total Dividend Equivalent Liability |  |  |  |  |  |  |  |  |  |  | $ 2,320,000 |  |  |  | 2,161,000 |  |  |  |  |  |  |  |  |  |  |  | $ 2,320,000 | 2,161,000 |
CommonStockDividendsPerShareDeclared | $ 0.09 | $ 0.09 | $ 0.09 | $ 0.09 | $ 0.09 |  | $ 0.075 | $ 0.2 | $ 0.075 | $ 0.075 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.36 |  | $ 0.3
Dividend payments | $ 12,440,990 | $ 12,366,985 | $ 12,486,825 | $ 12,475,445 | $ 12,633,039 |  | $ 2,921,727 | $ 7,791,075 | $ 2,920,860 | $ 2,915,952 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 49,770,000 | $ 29,296,000 | $ 8,666,000
Shares of stock deemed repurchased |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 506,000 | 169,000 | 232,000
Amount recorded as financing activity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ (5,186,000) | $ (2,565,000) | $ (2,268,000)
The total cost to repurchase |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (29,407,000) | (10,675,000) | 0
Dividends paid on preferred stock |  |  |  |  |  | $ 236,806 |  |  |  |  |  |  |  |  |  | $ 687,500 |  | $ 550,000 |  | $ 550,000 |  | $ 550,000 | $ 0 | $ 0 | $ 0 | $ 0 | $ 0 | 2,574,000 | 1,788,000
Employee stock purchase plan, authorized shares |  |  |  |  |  |  |  |  |  |  | 1,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,000,000 |  |
Stock Issued During Period Value Employee Stock Purchase Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,428,000 | 182,000 | 379,000
Total Non cash compensation expense recognized |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 11,989,000 | 6,239,000 | 4,218,000
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 | $ 0 | $ 0 | $ 0 | $ 0 |  |  |
PaymentsOfDividendsAbstract |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments of Dividends, Common Stock | $ 12,440,990 | $ 12,366,985 | $ 12,486,825 | $ 12,475,445 | $ 12,633,039 |  | $ 2,921,727 | $ 7,791,075 | $ 2,920,860 | $ 2,915,952 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 49,770,000 | 29,296,000 | 8,666,000
PaymentsOfDividendsPreferredStockAndPreferenceStock |  |  |  |  |  |  |  |  |  |  | $ 0 | $ 0 | $ 0 | $ 0 | $ 924,000 |  | $ 550,000 |  | $ 550,000 |  | $ 550,000 |  |  |  |  |  | 0 | $ 2,574,000 | $ 1,788,000
Treasury Stock Line Items |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Repurchase Prgram Authorized Amount |  |  |  |  |  |  |  |  |  |  | $ 100,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 100,000,000 |  |
Average Cost per share of Acquired Treasury Shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 9.11 |  |
ESPP [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends And Shares Activitiy [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period Shares Employee Stock Purchase Plans |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 228,000 | 15,000 | 32,000
Total Non cash compensation expense recognized |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 252,000 | $ 32,000 | $ 67,000

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- Definition Dividend equivalent liability non current include the right, upon vesting, to receive a cash payment equal to the aggregate amount of dividends, if any, that holders would have received on the shares of common stock underlying their RSUs if such RSUs had been vested during the period + References No definition available. + Details
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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4332-108586 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4313-108586 + Details
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- Definition Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21463-112644 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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