Investments in Affiliates and Other Related Party Transactions - Amounts Recorded in Consolidated Balance Sheet for Affiliates (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Equity Method Investments and Joint Ventures [Abstract]
Aggregate investment in affiliates	$ 153.5	$ 156.5
Receivables due from affiliates (including notes and advances)	121.8	95.5
Payables due to affiliates	$ 4.3	$ 7.7

Amount of payable due to an entity that is affiliated with the reporting entity by means of direct or indirect ownership.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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Reference 5: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant