Related Party Transactions (Equity Method Investment) (Narrative) (Details) - 2017 Acquisitions [Member] - Equity Method Investee [Member] - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Equity method investment, ownership percentage	40.00%
Advances outstanding from related party, net (in dollars)	$ 0.1	$ 0.3

For an unclassified balance sheet, amount of receivables due from an entity that is affiliated with the reporting entity by means of direct or indirect ownership.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant