v2.4.0.6

Fair value of financial instruments (Tables) | 3 Months Ended
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Mar. 31, 2013
Fair value of financial instruments |
Schedule of recurring measurements of fair value hierarchy of financial assets and liabilities |
|  | March 31, 2013 |
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(in millions) |  | Level 1 |  | Level 2 |  | Level 3 |  | Total |
Assets: |  |  |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents |  | $ | 85.7 |  | $ | — |  | $ | — |  | $ | 85.7 |
Restricted cash |  |  | 43.5 |  |  | — |  |  | — |  |  | 43.5 |
Derivative instruments asset |  |  | — |  |  | 14.8 |  |  | — |  |  | 14.8 |
Total |  | $ | 129.2 |  | $ | 14.8 |  | $ | — |  | $ | 144.0 |
Liabilities: |  |  |  |  |  |  |  |  |  |  |  |  |
Derivative instruments liability |  | $ | — |  | $ | 136.1 |  | $ | — |  | $ | 136.1 |
Total |  | $ | — |  | $ | 136.1 |  | $ | — |  | $ | 136.1 |
|  | December 31, 2012 |
--- | --- | --- | ---
|  | Level 1 |  | Level 2 |  | Level 3 |  | Total |
Assets: |  |  |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents |  | $ | 60.2 |  | $ | — |  | $ | — |  | $ | 60.2 |
Restricted cash |  |  | 28.6 |  |  | — |  |  | — |  |  | 28.6 |
Derivative instruments asset |  |  | — |  |  | 20.6 |  |  | — |  |  | 20.6 |
Total |  | $ | 88.8 |  | $ | 20.6 |  | $ | — |  | $ | 109.4 |
Liabilities: |  |  |  |  |  |  |  |  |  |  |  |  |
Derivative instruments liability |  | $ | — |  | $ | 151.1 |  | $ | — |  | $ | 151.1 |
Total |  | $ | — |  | $ | 151.1 |  | $ | — |  | $ | 151.1 |

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- Definition Tabular disclosure of assets and liabilities, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19190-110258 + Details
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