RETIREMENT PLANS: (Details 3)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Principal assumptions used (benefit obligation):
Discount rate (percent)	3.22%	4.22%
Rate of increase in compensation levels (percent)	3.00%	3.00%
Principal assumptions used (net periodic benefit):
Discount rate	4.22%	3.60%
Rate of increase in compensation levels	3.00%	3.00%
Expected long-term rate of return on plan assets (percent)	6.00%	6.00%

Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

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Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
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Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan.

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Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

+ References

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-Publisher FASB
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-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
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Weighted average rate of compensation increase used to determine net periodic benefit cost of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(2)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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