RETIREMENT BENEFITS - Pension Plan's Asset Allocation (Detail)	Dec. 31, 2019	Dec. 31, 2018
Cash and cash equivalent
Defined Benefit Plan Disclosure [Line Items]
Allocation	3.00%	1.00%
Pension Plan \| Fixed income funds
Defined Benefit Plan Disclosure [Line Items]
Allocation	31.00%	34.00%
Pension Plan \| Domestic equity funds - large cap
Defined Benefit Plan Disclosure [Line Items]
Allocation	34.00%	29.00%
Pension Plan \| Domestic equity funds - small cap
Defined Benefit Plan Disclosure [Line Items]
Allocation	5.00%	6.00%
Pension Plan \| International equity funds
Defined Benefit Plan Disclosure [Line Items]
Allocation	17.00%	20.00%
Pension Plan \| Hedge funds, private equity, real estate, commodities
Defined Benefit Plan Disclosure [Line Items]
Allocation	10.00%	10.00%
Pension Plan \| Minimum \| Fixed income:
Defined Benefit Plan Disclosure [Line Items]
Targeted Allocation	25.00%	25.00%
Pension Plan \| Minimum \| Equity securities:
Defined Benefit Plan Disclosure [Line Items]
Targeted Allocation	35.00%	35.00%
Pension Plan \| Minimum \| Other:
Defined Benefit Plan Disclosure [Line Items]
Targeted Allocation	4.00%	4.00%
Pension Plan \| Maximum \| Fixed income:
Defined Benefit Plan Disclosure [Line Items]
Targeted Allocation	55.00%	55.00%
Pension Plan \| Maximum \| Equity securities:
Defined Benefit Plan Disclosure [Line Items]
Targeted Allocation	65.00%	65.00%
Pension Plan \| Maximum \| Other:
Defined Benefit Plan Disclosure [Line Items]
Targeted Allocation	15.00%	15.00%

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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)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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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
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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