SHAREHOLDERS EQUITY - Stock based compensation - Restricted Stock Awards (Details) - USD ($) $ / shares in Units, $ in Millions	9 Months Ended	12 Months Ended
Sep. 30, 2018	Dec. 31, 2017
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued		105,264
Value of shares issued		$ 3.0
Weighted-average grant date fair value (in dollars per share)	$ 28.50
Recognized compensation expense	$ 0.2
Unrecognized compensation expense	$ 2.8
Unrecognized compensation expense recognition period (in years)	4 years
Number of shares vested	10,526
Employee service period
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued		52,632
Value of shares issued		$ 1.5
Vesting period (in years0		5 years
Performance of mortgage division
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued		52,632
Value of shares issued		$ 1.5

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.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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Aggregate value of stock related to Restricted Stock Awards issued during the period.

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