STOCK OPTIONS - Summary of status of Salisbury's outstanding stock options (Details) - Stock options - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Number, beginning of period	22,545	40,500
Weighted average exercise price, beginning of period	$ 17.04	$ 21.73
Number of options, granted
Weighted average exercise price, granted
Number of options, exercised	(4,725)	(9,155)
Weighted average exercise price, exercised	$ 17.04	$ 24.26
Number of options, forfeited or expired		(8,800)
Weighted average exercise price, forfeited or expired		$ 31.11
Number, end of period	17,820	22,545
Weighted average exercise price, end of period	$ 17.04	$ 17.04
Weighted average remaining contractual term	4 years	5 years
Aggregate intrinsic value	$ 510	$ 456

For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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Gross number of share options (or share units) granted during the period.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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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.

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Number of share options (or share units) exercised during the current period.

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