SECURITIES: (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Amortized cost and fair value of investments classified as available for sale
TOTAL	$ 811,369	$ 855,521
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	13,097	12,618
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	9,535	14,414
Securities available-for-sale	814,931	853,725
U.S. Government entity mortgage-backed securities
Amortized cost and fair value of investments classified as available for sale
TOTAL	13,989	13,594
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	24	32
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	318	377
Securities available-for-sale	13,695	13,249
Mortgage-backed securities, residential
Amortized cost and fair value of investments classified as available for sale
TOTAL	215,079	261,878
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	2,071	3,200
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	1,812	4,073
Securities available-for-sale	215,338	261,005
Mortgage-backed securities, commercial
Amortized cost and fair value of investments classified as available for sale
TOTAL	1	4
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	0	0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	0	0
Securities available-for-sale	1	4
Collateralized mortgage obligations
Amortized cost and fair value of investments classified as available for sale
TOTAL	346,005	353,499
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	370	1,021
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	6,705	6,344
Securities available-for-sale	339,670	348,176
State and municipal obligations
Amortized cost and fair value of investments classified as available for sale
TOTAL	227,651	217,365
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	4,671	3,954
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	700	2,396
Securities available-for-sale	231,622	218,923
Collateralized debt obligations
Amortized cost and fair value of investments classified as available for sale
TOTAL	8,644	9,181
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	5,961	4,411
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	0	1,224
Securities available-for-sale	$ 14,605	$ 12,368

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26610-111562

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
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