BENEFIT PLANS: Defined Benefit Plan, Information about Plan Assets, Allocation Percentages (Details) - Pension Plan	Dec. 31, 2019
Defined Benefit Plan Disclosure
Target Allocation Percentage of Assets	100.00%
Actual Plan Asset Allocations	100.00%
Debt Securities
Defined Benefit Plan Disclosure
Target Allocation Percentage of Assets	24.00%
Actual Plan Asset Allocations	23.00%
Equity Securities
Defined Benefit Plan Disclosure
Target Allocation Percentage of Assets	56.00%
Actual Plan Asset Allocations	59.00%
Real Estate
Defined Benefit Plan Disclosure
Target Allocation Percentage of Assets	7.00%
Actual Plan Asset Allocations	6.00%
Other plan assets
Defined Benefit Plan Disclosure
Target Allocation Percentage of Assets	13.00%
Actual Plan Asset Allocations	12.00%

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Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
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Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 1
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