Employee Benefits (Other Post-retirement Plan Narrative) (Details)	12 Months Ended
Dec. 31, 2018 subsidiary
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Number Of Subsidiaries Company Provides Post Retirement Healthcare Benefit	2

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.

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