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EMPLOYEE BENEFIT PLANS - 401(k) Plan and Stock Incentive Plan (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
EMPLOYEE BENEFIT PLANS |  |  |
Maximum percentage of annual contribution per employee |  | 25.00% |
Percentage of employer matching contribution | 100.00% | 50.00% |
Threshold limit percentage of employee compensation |  | 6.00% |
Maximum period of vesting in contribution of employees | 3 years |  |
Employer matching contribution | $ 796,000 | $ 319,000 | $ 317,000
Stock Incentive Plans Member |  |  |
EMPLOYEE BENEFIT PLANS |  |  |
Stock authorized (in shares) | 3,000,000 |  |
Expiration term of share-based compensation plans | 10 years |  |
Number of shares available for grants | 1,742,900 |  |
Pre-tax stock-based employee compensation expense | $ 2,123,000 | 2,089,000 | 2,682,000
After tax stock-based employee compensation expense | $ 1,656,000 | $ 1,629,000 | $ 1,729,000

X
- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements before tax (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. + References No definition available. + Details
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- Definition This element represents the threshold limit in percentage of employees' compensation. + References No definition available. + Details
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Period Type: | duration

X
- Definition This element represents the maximum period of vesting in contribution of employees. + References No definition available. + Details
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- Definition Amount, after tax, of expense for award under share-based payment arrangement. + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount of discretionary contributions made by an employer to a defined contribution plan. + References No definition available. + Details
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Balance Type: | debit
Period Type: | duration

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- Definition Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan. + References No definition available. + Details
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- Definition Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan. + References No definition available. + Details
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- Definition Number of shares authorized for issuance under share-based payment arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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X
- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Details
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