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SUBSEQUENT EVENTS (Details) (USD $) In Millions, except Share data, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009
Subsequent Event [Line Items] |  |  |
Dividend declared (in dollars per share) | $ 0 | $ 0 | $ 2.35
Underwritten Public Offering [Member] |  |  |
Subsequent Event [Line Items] |  |  |
Subsequent event, amount | $ 75.9 |  |
Subsequent event, shares issued | 5,500,000 |  |
Dividend Declared [Member] |  |  |
Subsequent Event [Line Items] |  |  |
Dividend declared (in dollars per share) | $ 0.30 |  |
Date dividend declared | 2012-02 |  |
Date dividend paid | Mar. 31, 2012 |  |

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- Definition 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 + Details
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