Significant Accounting Policies Insurance (Details) $ in Millions	Dec. 31, 2018 USD ($)
Liability Policies [Member]
SEC Schedule, 12-18, Supplemental Information, Property-Casualty Insurance Underwriters [Line Items]
Self-insured retention, maximum per incident	$ 2.5
Property policies [Member]
SEC Schedule, 12-18, Supplemental Information, Property-Casualty Insurance Underwriters [Line Items]
Self-insured retention, maximum per incident	$ 2.5

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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