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Fair Values of Financial Instruments (Details 2) (USD $)
In Millions, unless otherwise specified |
12 Months Ended | |
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Dec. 31, 2011
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Dec. 31, 2010
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| Fair Values of Financial Instruments | ||
| Marketable debt securities, available-for-sale, amortized cost basis | $ 41.2 | $ 61.9 |
| Marketable debt securities, available-for-sale, fair value | 43.3 | 66.7 |
| Contractual maturities of marketable debt securities range, low | October 1, 2012 | |
| Contractual maturities of marketable debt securities range, high | April 15, 2016 | |
| Proceeds from sale of marketable debt securities | 23.1 | |
| Gain from the sale of marketable debt security | $ 1.8 |
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- Definition
This item represents the total of all debt securities grouped by maturity dates, at cost, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments, as defined), and fair value hedge accounting adjustments, if any, which are classified neither as held-to-maturity nor trading securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The latest date, in a range of maturity dates, that a debt security categorized as neither trading nor held-to-maturity is scheduled to be repaid. No definition available.
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- Definition
The earliest date, in a range of maturity dates, that a debt security categorized as neither trading nor held-to-maturity is scheduled to be repaid. No definition available.
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- Definition
This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition
The cash inflow associated with the sale of debt securities classified as available-for-sale securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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