Pension Plans (Summary of Target Allocations and Invested Asset Allocations) (Details) - Pension Plans [Member] - US [Member]	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Total Fixed Income and Equity Securities, TARGET LEVELS	100.00%
Total Fixed Income and Equity Securities	100.00%	100.00%
Money Market Funds
Defined Benefit Plan Disclosure [Line Items]
Total Fixed Income and Equity Securities, TARGET LEVELS	2.00%
Total Fixed Income and Equity Securities	2.00%	1.00%
Fixed Income Securities
Defined Benefit Plan Disclosure [Line Items]
Total Fixed Income and Equity Securities, TARGET LEVELS	85.00%
Total Fixed Income and Equity Securities	87.00%	84.00%
Domestic
Defined Benefit Plan Disclosure [Line Items]
Total Fixed Income and Equity Securities, TARGET LEVELS	12.00%
Total Fixed Income and Equity Securities	10.00%	12.00%
International
Defined Benefit Plan Disclosure [Line Items]
Total Fixed Income and Equity Securities, TARGET LEVELS	3.00%
Total Fixed Income and Equity Securities	3.00%	4.00%
Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Total Fixed Income and Equity Securities, TARGET LEVELS	15.00%
Total Fixed Income and Equity Securities	13.00%	16.00%
Fixed Maturities [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fixed Income and Equity Securities, TARGET LEVELS	83.00%
Total Fixed Income and Equity Securities	85.00%	83.00%

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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=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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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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