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

+ References

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

Date the declared dividend will be paid, in CCYY-MM-DD format.

+ References

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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

Date the dividend to be paid was declared, in CCYY-MM-DD format.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 32

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

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No definition available.

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Subsequent Events (Details Textual) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Subsequent Events (Textual) [Abstract]
Cash dividend payable amount per share	$ 0.11	$ 0.11	$ 0.22	$ 0.22
Common Stock class one and two [Member] \| Cash Dividend [Member]
Subsequent Events (Textual) [Abstract]
Cash dividend payable	$ 1,500
Cash dividend payable amount per share	$ 0.11
Date of announcement of dividend	Jul. 25, 2012
Date of payment of dividend	Aug. 24, 2012
Date of record of dividend	Aug. 10, 2012