Investment Income (Details Textual) (USD $)	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011
Investment income (Textual) [Abstract]
Significant investments	$ 0
Realized gain on sale of debt and equity investment available for sale	3,900,000
Realized gain from the sales of property	2,200,000
Realized losses on impairment of cost basis investments		1,200,000
Loan guarantee obligation		3,900,000
Realized gain from debt investment available for sale		$ 3,100,000

The difference between the sale price or salvage price and the book value of a property, plant, and equipment asset that was sold or retired during the reporting period. This element refers to the gain (loss).

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

Name:	us-gaap_GainLossOnSaleOfPropertyPlantEquipment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration