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Fair Value Measurements (Reconciliation of Fair Value Using Significant Unobservable Inputs ) (Details) (Convertible Preferred Stock [Member], USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2011 | Dec. 31, 2010
Convertible Preferred Stock [Member] |  |
Beginning balance | $ 78.2 |
Issuances |  | 75.0
Paid-in-kind dividends issued | 10.1 | 0.8
Less: paid-in-kind dividends payable, beginning balance | (2.4) |
Paid-in-kind dividends payable | 2.7 | 2.4
Transfer out of Level 3 | (88.6) |
Ending balance |  | $ 78.2

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- Definition Transfers out of liabilities measured at fair value and categorized within Level 3 of the fair value hierarchy that have taken place during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258 + Details
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- Definition Issues that have taken place during the period in relation to liabilities measured at fair value and categorized within Level 3 of the fair value hierarchy. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258 + Details
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- Definition This element represents a liability measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258 + Details
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- Definition Paid-in-kind dividends issued + References No definition available. + Details
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- Definition Paid in kind convertible preferred stock dividends payable + References No definition available. + Details
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- Definition Paid in kind convertible preferred stock dividends payable beginning balance + References No definition available. + Details
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