Fair value of financial instruments - recurring (Details) - USD ($) $ in Millions |
3 Months Ended | 12 Months Ended |
|---|---|---|
Mar. 31, 2016 |
Dec. 31, 2015 |
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| Assets: | ||
| Restricted cash | $ 10.0 | $ 15.2 |
| Recurring | ||
| Assets: | ||
| Cash and cash equivalents | 64.3 | 72.4 |
| Restricted cash | 10.0 | 15.2 |
| Derivative instruments asset | 0.6 | 0.3 |
| Total | 74.9 | 87.9 |
| Liabilities: | ||
| Derivative instruments liability | 62.0 | 57.5 |
| Total | 62.0 | 57.5 |
| Recurring | Credit valuation adjustments | ||
| Liabilities: | ||
| Net increase in fair value | 5.1 | 3.8 |
| Pre-tax gain in other comprehensive income | 0.5 | 0.4 |
| Gain in change in fair value of derivatives | 4.6 | 3.4 |
| Recurring | Level 1 | ||
| Assets: | ||
| Cash and cash equivalents | 64.3 | 72.4 |
| Restricted cash | 10.0 | 15.2 |
| Total | 74.3 | 87.6 |
| Recurring | Level 2 | ||
| Assets: | ||
| Derivative instruments asset | 0.6 | 0.3 |
| Total | 0.6 | 0.3 |
| Liabilities: | ||
| Derivative instruments liability | 62.0 | 57.5 |
| Total | $ 62.0 | $ 57.5 |
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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The increase (decrease) during the period in the net carrying value of derivative instruments reported as assets and liabilities that are due to be disposed of within one year (or the normal operating cycle, if longer). No definition available.
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- Definition Fair value of financial and nonfinancial obligations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against short-term borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. For a classified balance sheet represents the current portion only (the noncurrent portion has a separate concept); there is a separate and distinct element for unclassified presentations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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