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EMPLOYEE BENEFIT PLANS Table 6 - Major Classes of Plan Assets Measured at Fair Value (Details) - Pension Plans (The Pension Plan, Excess Pension Plan and SERP) [Member] - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 129,878	$ 107,644	$ 87,706
Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	54,525	42,831
Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	75,353	64,813
Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Cash equivalent securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	381	738
Cash equivalent securities [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	381	738
Cash equivalent securities [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Cash equivalent securities [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. large cap equity fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	75,353	64,813
U.S. large cap equity fund [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
U.S. large cap equity fund [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	75,353	64,813
U.S. large cap equity fund [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International stock index fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	14,480	10,459
International stock index fund [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	14,480	10,459
International stock index fund [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International stock index fund [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Bond market index fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	39,664	31,634
Bond market index fund [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	39,664	31,634
Bond market index fund [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Bond market index fund [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0	$ 0

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- Definition

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+ References

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- Definition

Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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