Equity-method investments Additional Information (Details) (HC2 Holdings Inc. [Member], USD $)	Sep. 30, 2014	Jan. 03, 2014
HC2 Holdings Inc. [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Quoted Market Value	$ 26.5
Business Acquisition, Percentage of Voting Interests Acquired	24.70%	40.50%

This item represents the aggregate value of each identified investment accounted for under the equity method of accounting based on the quoted market price for those investments in common stock for which a quoted market price is available.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

Name:	us-gaap_EquityMethodInvestmentQuotedMarketValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant