Goodwill and Intangible Assets (Tables)	3 Months Ended
Mar. 31, 2013
Goodwill and Intangible Assets [Abstract]
Estimated annual amortization expense	Estimated annual amortization expense

Tabular disclosure of the estimated aggregate amortization expense for intangible assets subject to amortization for each of the five succeeding fiscal years.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16323-109275

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Balance Type:	na
Period Type:	duration