STOCKHOLDERS' EQUITY - Stock Options (Details) - USD ($) |
3 Months Ended | 6 Months Ended | 12 Months Ended | ||
|---|---|---|---|---|---|
Jun. 30, 2019 |
Jun. 30, 2018 |
Jun. 30, 2019 |
Jun. 30, 2018 |
Dec. 31, 2018 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||||
| Granted (in shares) | 0 | 0 | 0 | 0 | |
| Options | |||||
| Outstanding at period start (in shares) | 112,094 | ||||
| Exercised (in shares) | (21,409) | ||||
| Outstanding at period end (in shares) | 90,685 | 90,685 | 112,094 | ||
| Weighted-Average Exercise Price | |||||
| Outstanding at period start, Weighted-Average Exercise Price (in dollars per share) | $ 30.32 | ||||
| Exercised, Weighted-Average Exercise Price (in dollars per share) | 30.69 | ||||
| Outstanding at period end, Weighted-Average Exercise Price (in dollars per share) | $ 30.23 | $ 30.23 | $ 30.32 | ||
| Contractual Terms (in years) | 1 year 4 months 24 days | 1 year 9 months 18 days | |||
| Stock Option | |||||
| Weighted-Average Exercise Price | |||||
| Vesting period (in years) | 3 years | ||||
| Stock-based compensation expense | $ 0 | $ 0 | $ 0 | $ 0 | |
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- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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. No definition available.
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- Definition Gross number of share options (or share units) granted during the period. No definition available.
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- Definition Number of options outstanding, including both vested and non-vested options. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition Weighted average price at which option holders acquired shares when converting their stock options into shares. No definition available.
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- Definition Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of share options (or share units) exercised during the current period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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