SHAREHOLDERS' EQUITY - Share Buyback (Details) - USD ($)	3 Months Ended							12 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	[1]	Dec. 31, 2017	Sep. 12, 2019	Sep. 05, 2017
Treasury Stock, Number of Shares and Restriction Disclosures [Abstract]
Treasury stock, shares acquired (in shares)	3,590	3,590
Treasury stock, value acquired, cost method	$ 774,000	$ 0	$ 0	$ 0	$ 8,489,000	$ 10,525,000	$ 1,401,000	$ 7,518,000	$ 20,412,000
New share repurchase program
Treasury Stock, Number of Shares and Restriction Disclosures [Abstract]
Authorized amount under the share repurchase program												$ 5,000,000	$ 5,000,000
Treasury stock, shares acquired (in shares)											17,364
Treasury stock acquired, average cost per share (in dollars per share)											$ 11.95
Treasury stock, value acquired, cost method											$ 207,000

[1] * Amounts restated See footnotes 2 and 16 for more information.