FAIR VALUES OF FINANCIAL INSTRUMENTS: (Details 1) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Total realized/unrealized gains or losses
Beginning balance, January 1	$ 19,600	$ 21,203
Included in earnings	0	0
Included in other comprehensive income	(2,066)	138
Purchases	0	0
Settlements	(956)	(1,741)
Ending balance, December 31	16,578	19,600
State and municipal obligations
Total realized/unrealized gains or losses
Beginning balance, January 1	4,725	5,900
Included in earnings	0
Included in other comprehensive income	0
Purchases	0	0
Settlements	(515)	(1,175)
Ending balance, December 31	4,210	4,725
Collateralized debt obligations
Total realized/unrealized gains or losses
Beginning balance, January 1	14,875	15,303
Included in earnings	0	0
Included in other comprehensive income	(2,066)	138
Settlements	(441)	(566)
Ending balance, December 31	$ 12,368	$ 14,875

Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1a)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy.

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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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