Fair Value Measurements (Details Textual) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Derivative [Line Items]
Derivative Liability, Fixed Rate Debt, Carrying Value	$ 603.4	$ 505.6
Derivative Liability, Fixed Rate Debt, Fair Value	594.8	516.5
Derivative Liability, Variable Rate Debt, Fair Value	$ 14.0	$ 14.0

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.

Name:	us-gaap_DerivativeLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration