Aggregate dividends declared during the period for each share of common stock outstanding.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187085-122770

Name:	us-gaap_CommonStockDividendsPerShareDeclared
Namespace Prefix:	us-gaap
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

Stockholders' Equity (Dividends Information) (Details) (USD $)	0 Months Ended	3 Months Ended							9 Months Ended	12 Months Ended
	Oct. 12, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Sep. 30, 2011	Dec. 31, 2010
Stockholders' Equity
Dividends paid per share		$ 0.13	$ 0.13	$ 0.25	$ 0.21	$ 0.21	$ 0.00	$ 0.20		$ 0.62
Dividend declared per share	$ 0.14
Dividend paid and declared per share									$ 0.65