Description of Business and Summary of Significant Accounting Policies (Details 8) (Auction Rate Securities, Income approach valuation model)	12 Months Ended
Dec. 31, 2013
Minimum
Fair value inputs
Fair value inputs, discount rate (in hundredths)	3.00%
Fair value inputs, term of auction rate securities	6 years
Maximum
Fair value inputs
Fair value inputs, discount rate (in hundredths)	7.00%
Fair value inputs, term of auction rate securities	8 years

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bbb)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

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