Consolidated Statements of Comprehensive Income (Parenthetical) (USD $) In Millions	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Consolidated Statements of Comprehensive Income
Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax	$ 0.3	$ 0	$ 0.2	$ 2.6
Other than Temporary Impairment of Available-for-Sale Securities Included in Net Income, Tax	0	0	0	0
Realized Gain (Loss) on Available-for-Sale Securities Included in Net Income, Tax	$ 3.5	$ 0	$ 3.5	$ 0

Tax effect on the reclassification adjustment for gains or losses realized upon the sale of securities during the period.

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 38

-Subparagraph c(3)

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 130

-Paragraph 25

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- Definition

Tax effect on the reclassification adjustment for losses realized upon the write-down of securities.

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Tax effect on gross appreciation or the gross loss in value of the total of unsold securities during the period being reported on.

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