BENEFIT PLANS: Defined Benefit Plan, Information about Plan Assets, Allocation Percentages (Details) - Pension Plan	12 Months Ended
Dec. 31, 2015
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	25.00%
Equity Securities
Defined Benefit Plan Disclosure
Target Allocation Percentage of Assets	54.00%
Actual Plan Asset Allocations	55.00%
Real Estate
Defined Benefit Plan Disclosure
Target Allocation Percentage of Assets	6.00%
Actual Plan Asset Allocations	7.00%
Other plan assets
Defined Benefit Plan Disclosure
Target Allocation Percentage of Assets	16.00%
Actual Plan Asset Allocations	13.00%

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Target allocation of investments of this type to total plan assets presented on a weighted average basis.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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