Investments in Affiliated Companies (Future Debt Maturities) (Details 8) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Schedule of Equity Method Investments [Line Items]
2016	$ 302.6
2017	515.7
2018	550.0
2019	350.0
2020	557.8
Thereafter	2,010.1
Total debt principal	$ 4,286.2	$ 4,205.4
RRPF Joint Ventures [Member]
Schedule of Equity Method Investments [Line Items]
Long-term Debt, Contingent Payment of Principal or Interest	335
2016	$ 618.1
2017	96.9
2018	54.4
2019	470.7
2020	265.7
Thereafter	943.9
Total debt principal	$ 2,449.7

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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