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Consolidating Financial Statements (Details Textual) | Dec. 31, 2011
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On conversion of 4.75% convertible senior notes due 2014 [Member] |
Financial Statements (Textual) [Abstract] |
Debt Instrument, Interest Rate, Stated Percentage | 4.75%
On conversion of 7.25% convertible Senior notes due 2018 [Member] |
Financial Statements (Textual) [Abstract] |
Debt Instrument, Interest Rate, Stated Percentage | 7.25%

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- Definition Interest rate stated in the contractual debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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