Investments in Marketable Debt Securities - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified |
6 Months Ended | |||
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Jun. 30, 2012
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Jun. 30, 2011
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Jun. 30, 2012
Variable Rate Demand Obligation
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Dec. 31, 2011
Variable Rate Demand Obligation
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Schedule of Available-for-sale Securities [Line Items] | ||||
Marketable securities sales and maturities | $ 297.5 | $ 636.4 | ||
Gross realized gains from sales of marketable securities | 1.5 | 0.6 | ||
Gross realized loss from sales of marketable securities | 0.1 | 0.4 | ||
Marketable debt securities in an unrealized loss position for greater than 12 months | 2.5 | 1.0 | ||
Marketable debt securities in an unrealized loss position for greater than 12 months, unrealized losses | 0.10 | 0.01 | ||
Marketable debt securities | $ 1.5 | $ 7.1 |
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- Definition
Available for Sale Securities Debt Securities Continuous Unrealized Loss Twelve Months or Longer No definition available.
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- Definition
This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for twelve months or longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Total debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale which are intended to be held for less than one year or the normal operating cycle, whichever is longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The cash inflow associated with the aggregate amount received by the entity through sale or maturity of marketable securities (held-to-maturity or available-for-sale) during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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