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 - Summary of plan weighted average asset allocation by asset category along with target allocation for 2019 (Details 6) - Retirement Income Plan	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Percentage of Plan Assets	100.00%	100.00%
Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Percentage of Plan Assets	3.00%	2.80%
Cash and cash equivalents \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Target Allocation for 2019 minimum percentage	0.00%
Cash and cash equivalents \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Target Allocation for 2019 minimum percentage	3.00%
Fixed income securities
Defined Benefit Plan Disclosure [Line Items]
Percentage of Plan Assets	29.10%	20.70%
Fixed income securities \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Target Allocation for 2019 minimum percentage	15.00%
Fixed income securities \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Target Allocation for 2019 minimum percentage	100.00%
Domestic Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Percentage of Plan Assets	39.50%	23.80%
Domestic Equity Securities \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Target Allocation for 2019 minimum percentage	0.00%
Domestic Equity Securities \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Target Allocation for 2019 minimum percentage	40.00%
International Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Percentage of Plan Assets	19.00%	42.40%
International Equity Securities \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Target Allocation for 2019 minimum percentage	0.00%
International Equity Securities \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Target Allocation for 2019 minimum percentage	30.00%
Investments measured at net asset value
Defined Benefit Plan Disclosure [Line Items]
Percentage of Plan Assets	9.40%	10.30%
Investments measured at net asset value \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Target Allocation for 2019 minimum percentage	0.00%
Investments measured at net asset value \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Target Allocation for 2019 minimum percentage	12.00%