Basis of Presentation - Cash Flows and Cash, Cash Equivalents, Restricted Cash and Marketable Securities (Details) - USD ($) $ in Millions |
6 Months Ended | |||
|---|---|---|---|---|
Jun. 30, 2018 |
Jun. 30, 2017 |
Dec. 31, 2017 |
Dec. 31, 2016 |
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| New Accounting Pronouncements or Change in Accounting Principle [Line Items] | ||||
| Decrease in cash used in investing activities | $ (606.0) | $ (590.5) | ||
| Cash and cash equivalents | 61.3 | 36.0 | $ 83.3 | $ 67.8 |
| Restricted cash and marketable securities | 116.2 | 93.3 | 141.1 | 90.5 |
| Less: restricted marketable securities | (44.8) | (45.1) | (45.3) | (45.3) |
| Cash, cash equivalents, restricted cash and restricted cash equivalents | $ 132.7 | 84.2 | $ 179.1 | $ 113.0 |
| Accounting Standards Update 2016-18 | ||||
| New Accounting Pronouncements or Change in Accounting Principle [Line Items] | ||||
| Decrease in cash used in investing activities | $ 3.0 | |||
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- Definition Amount 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. Excludes cash and cash equivalents within disposal group and discontinued operation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, 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://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition The noncurrent cash, cash equivalents and investments that is restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits classified as long-term; that is not expected to be released from such existing restrictions within one year of the balance sheet date or operating cycle, whichever is longer. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. Includes noncurrent cash equivalents and investments that are similarly restricted as to withdrawal, usage or disposal. No definition available.
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- Definition This element represents the noncurrent portion of investments which are not defined as or included in marketable (debt, equity, or other) securities that are pledged or subject to withdrawal restrictions. No definition available.
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- Details
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