FAIR VALUES OF FINANCIAL INSTRUMENTS: (Details 1) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Total realized/unrealized gains or losses
Beginning balance, January 1	$ 6,184	$ 6,393
Included in earnings	0	0
Included in other comprehensive income	(483)	498
Purchases	0	0
Settlements	(670)	(707)
Ending balance, December 31	5,031	6,184
State and municipal obligations
Total realized/unrealized gains or losses
Beginning balance, January 1	2,565	3,135
Included in earnings	0	0
Included in other comprehensive income	0
Purchases	0	0
Settlements	(670)	(570)
Ending balance, December 31	1,895	2,565
Collateralized debt obligations
Total realized/unrealized gains or losses
Beginning balance, January 1	3,619	3,258
Included in earnings	0	0
Included in other comprehensive income	(483)	498
Settlements	0	(137)
Ending balance, December 31	$ 3,136	$ 3,619

Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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Amount of gain (loss) recognized in other comprehensive income (OCI) from asset measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1a)
-URI http://asc.fasb.org/extlink&oid=117815213&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

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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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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.

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