Leases - Capital Leasers - Additional Information (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017
Capital Leased Assets [Line Items]
Capital lease term	49 years
Capital Lease Obligations
Capital Leased Assets [Line Items]
Repayments capital lease obligations	$ 1.9	$ 1.9

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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