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Fair Value Disclosures (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2013
Fair Value Disclosures (Additional Textual) [Abstract]
Cash equivalents consisting of money market funds with maturities	90 days	90 days
Transfers of assets between fair value hierarchy levels	$ 0	$ 0
Money Market Funds
Fair Value Disclosures (Textual) [Abstract]
Cash equivalents consisting of money market funds	$ 18.6	$ 18.6

X

- Definition

Cash equivalents consisting of money market funds with maturities.

+ References

No definition available.

+ Details

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X

- Definition

Fair value assets between hierarchy levels transfers amount.

+ References

No definition available.

+ Details

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- Details

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X

- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

-URI http://asc.fasb.org/extlink&oid=6506951



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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

-URI http://asc.fasb.org/extlink&oid=6507016

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