INVESTMENT SECURITIES: (Details 1) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Dec. 31, 2017	Jun. 30, 2018
Fair Value, Less than 12 Months	$ 26,470	$ 26,737
Unrealized Losses, Less than 12 Months	(284)	(749)
Fair Value, 12 Months or More	29,456	31,814
Unrealized Losses, 12 Months or More	(726)	(1,345)
Fair Value, Total	55,926	58,551
Unrealized Losses, Total	(1,010)	(2,094)
US Government Agencies [Member]
Fair Value, Less than 12 Months	7,840	9,751
Unrealized Losses, Less than 12 Months	(69)	(132)
Fair Value, 12 Months or More	7,189	9,433
Unrealized Losses, 12 Months or More	(152)	(312)
Fair Value, Total	15,029	19,184
Unrealized Losses, Total	(221)	(444)
Taxable Municipals
Fair Value, Less than 12 Months	2,403	3,527
Unrealized Losses, Less than 12 Months	(44)	(120)
Fair Value, 12 Months or More	767	750
Unrealized Losses, 12 Months or More	(34)	(50)
Fair Value, Total	3,170	4,277
Unrealized Losses, Total	(78)	(170)
Corporate Bonds
Fair Value, Less than 12 Months	1,507	2,393
Unrealized Losses, Less than 12 Months	(26)	(138)
Fair Value, 12 Months or More
Unrealized Losses, 12 Months or More
Fair Value, Total	1,507	2,393
Unrealized Losses, Total	(26)	(138)
Mortgage Backed Securities [Member]
Fair Value, Less than 12 Months	14,720	11,066
Unrealized Losses, Less than 12 Months	(145)	(359)
Fair Value, 12 Months or More	21,500	21,631
Unrealized Losses, 12 Months or More	(540)	(983)
Fair Value, Total	36,220	32,697
Unrealized Losses, Total	$ (685)	$ (1,342)