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=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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- 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=118255775&loc=d3e1928-114920

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Retirement Plans - Schedule of Asset Allocations for Pension Plans (Detail)	Dec. 31, 2020	Dec. 31, 2019
Equity securities
Defined Benefit Plan Disclosure [Line Items]
Percentage of Plan Assets	63.00%	60.00%
Debt securities
Defined Benefit Plan Disclosure [Line Items]
Percentage of Plan Assets	36.00%	37.00%
Cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Percentage of Plan Assets	1.00%	3.00%
Minimum \| Equity securities
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	45.00%
Minimum \| Debt securities
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	30.00%
Minimum \| Cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	0.00%
Maximum \| Equity securities
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	65.00%
Maximum \| Debt securities
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	50.00%
Maximum \| Cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	10.00%