Fair Values (Details 3) (USD $) In Thousands	9 Months Ended
Sep. 30, 2011
Fair value and unrealized gain (loss)
Fair Value, Less than 12 Months	$ 114,738
Unrealized Gains (Losses), Less than 12 Months	(7)
Fair Value, 12 Months or Greater	0
Unrealized Gains (Losses), 12 Months or Greater	0
Total Fair Value	114,738
Total Unrealized Gains (Losses)	(7)
Corporate bonds and notes [Member]
Fair value and unrealized gain (loss)
Fair Value, Less than 12 Months	114,738
Unrealized Gains (Losses), Less than 12 Months	(7)
Fair Value, 12 Months or Greater	0
Unrealized Gains (Losses), 12 Months or Greater	0
Total Fair Value	114,738
Total Unrealized Gains (Losses)	$ (7)

Fair value and unrealized gain (loss).

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- Definition

This item represents the excess of [amortized] cost over fair value of securities that have been in a loss position for twelve months or longer for those securities which are categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 03-1

-Paragraph 21

-Subparagraph a(2)

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS115-1/124-1

-Paragraph 17

-Subparagraph a(1)

+ Details

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- Definition

This item represents the excess of [amortized] cost over fair value of securities in a loss position and which are categorized neither as held-to-maturity nor trading securities.

+ References

+ Details

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- Definition

This item represents the fair value of securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

+ References

+ Details

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- Definition

This item represents the excess of [amortized] cost over fair value of securities that have been in a loss position for less than twelve months for those securities which are categorized neither as held-to-maturity nor trading securities.

+ References

+ Details

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- Definition

This item represents the fair value of securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months.

+ References

+ Details

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- Definition

This item represents the fair value of securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for twelve months or longer.

+ References

+ Details

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