Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

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=112275985&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)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

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- Definition

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
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

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EMPLOYEE BENEFIT PLANS - Weighted average asset allocation by asset category along with target allocation (Details) - Retirement Income Plan	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Percentage of plan assets	100.00%	100.00%
Target Allocation for 2019	100.00%
Cash and Cash Equivalents
Defined Benefit Plan Disclosure [Line Items]
Percentage of plan assets	3.00%	2.90%
Domestic Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Percentage of plan assets	39.50%	42.30%
International Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Percentage of plan assets	19.00%	20.70%
Fixed Income Securities
Defined Benefit Plan Disclosure [Line Items]
Percentage of plan assets	29.10%	23.80%
Investments measured at net asset value
Defined Benefit Plan Disclosure [Line Items]
Percentage of plan assets	9.40%	10.30%
Minimum \| Cash and Cash Equivalents
Defined Benefit Plan Disclosure [Line Items]
Target Allocation for 2019	0.00%
Minimum \| Domestic Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Target Allocation for 2019	0.00%
Minimum \| International Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Target Allocation for 2019	0.00%
Minimum \| Fixed Income Securities
Defined Benefit Plan Disclosure [Line Items]
Target Allocation for 2019	15.00%
Minimum \| Investments measured at net asset value
Defined Benefit Plan Disclosure [Line Items]
Target Allocation for 2019	0.00%
Maximum \| Cash and Cash Equivalents
Defined Benefit Plan Disclosure [Line Items]
Target Allocation for 2019	3.00%
Maximum \| Domestic Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Target Allocation for 2019	40.00%
Maximum \| International Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Target Allocation for 2019	30.00%
Maximum \| Fixed Income Securities
Defined Benefit Plan Disclosure [Line Items]
Target Allocation for 2019	100.00%
Maximum \| Investments measured at net asset value
Defined Benefit Plan Disclosure [Line Items]
Target Allocation for 2019	12.00%