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.

+ Details

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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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Pension and Other Postretirement Benefits - Schedule of Pension and Postretirement Plans Investment Policy and Weighted Average Asset Allocations (Details)	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, asset allocations	100.00%	100.00%
Equities
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, asset allocations	29.00%	28.00%
Equities \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Policy range	55.00%
Equities \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Policy range	20.00%
Fixed income
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, asset allocations	48.00%	47.00%
Fixed income \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Policy range	55.00%
Fixed income \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Policy range	25.00%
Other investments
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, asset allocations	23.00%	25.00%
Other investments \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Policy range	35.00%
Other investments \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Policy range	15.00%