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

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- Definition

Equity impact of common stock cash dividends declared by an entity during the period. This element includes paid and unpaid dividends declared during the period.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Subsequent Events (Details) (USD $) In Thousands, except Per Share data	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Dec. 31, 2010	Jun. 30, 2010
Subsequent Events
Cash dividends declared per common share (in dollars per share)	$ 0.125	$ 0.10	$ 0.25	$ 0.20	$ 0.20
Cash dividend declared on common stock			$ 12,526	$ 9,921	$ 9,917
Dividend declared, July 2011
Subsequent Events
Cash dividends declared per common share (in dollars per share)	$ 0.125
Cash dividend declared on common stock	$ 6,000