RETIREMENT BENEFITS - Multiemployer Pension Plans (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Contributions	$ 3,761	$ 4,785	$ 5,292
Central States, Southeast and Southwest Areas Pension Fund
Defined Benefit Plan Disclosure [Line Items]
EIN/Pension Plan Number	36-6044243/001
Pension Protection Act Zone Status	Red	Red
FIP / RP Status Pending / Implemented	Implemented
Contributions	$ 0	$ 1,166	1,797
Surcharge Imposed	No
United Food and Commercial Workers Local One Pension Fund
Defined Benefit Plan Disclosure [Line Items]
EIN/Pension Plan Number	16-6144007/001
Pension Protection Act Zone Status	Red	Red
FIP / RP Status Pending / Implemented	Implemented
Contributions	$ 240	$ 245	237
Surcharge Imposed	No
IAM National Pension Fund
Defined Benefit Plan Disclosure [Line Items]
EIN/Pension Plan Number	51-6031295/002
Pension Protection Act Zone Status	Red	Red
FIP / RP Status Pending / Implemented	Implemented
Contributions	$ 2,746	$ 2,667	$ 2,587
Surcharge Imposed	No
Multi employer funded status		87.00%	89.00%
All Other Pension Funds
Defined Benefit Plan Disclosure [Line Items]
Contributions	$ 775	$ 707	$ 671

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Multi employer Plans Status Funded Percentage

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- Definition

Amount of cost for employer contribution to multiemployer plan. Multiemployer plan includes, but is not limited to, pension plan determined to be individually significant and insignificant and other postretirement benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=35742348&loc=SL14450788-114948

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-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
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Indicates certified zone status of multiemployer pension plan determined to be individually significant. Acceptable values are "Green", "Yellow", "Orange", "Red", "Other", and "NA".

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Indicates whether funding improvement plan or rehabilitation plan was implemented or pending for multiemployer pension plan, determined to be individually significant. Acceptable values are "No", "Pending", "Implemented", "Other", and "NA".

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Indicates whether employer paid surcharge to multiemployer pension plan determined to be individually significant. Acceptable values are "No", "Yes" and "NA".

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