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Statement of Changes in Equity (Unaudited) (Parenthetical) (USD $) In Millions, except Per Share data, unless otherwise specified	9 Months Ended	12 Months Ended
	Sep. 30, 2011	Dec. 31, 2010
Statement of Changes in Equity [Abstract]
Common Shares Issued, issuance costs		$ 3.5
Return of Capital (in dollars per share)	$ 0.85	$ 1.7

X

- Definition

The per share reduction to additional paid in capital resulting from dividends legally declared or paid in excess of the balance in retained earnings. Such dividends may also be referred to as liquidating distributions or returns of capital.

+ References

No definition available.

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X

- Definition

The cash outflow for cost incurred directly with the issuance of an equity security.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 18, 19, 20

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3291-108585

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