Earnings per Share (Tables)	12 Months Ended
Dec. 31, 2012
Earnings Per Share [Abstract]
Numerators and Denominators of Basic and Diluted EPS Computations for Common Stock	Basic and diluted EPS are the same for each class of common stock because they are entitled to the same liquidation and dividend rights. The numerators and denomina

Tabular disclosure of the numerators and the denominators of the basic and diluted per-share (or per-unit) computations for income from continuing operations, including the effect that has been given to preferred dividends.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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