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Common Stock and Dividends (Details) (USD $) | 0 Months Ended | 1 Months Ended | 3 Months Ended |
--- | --- | --- | --- | ---
Apr. 19, 2013 | Apr. 09, 2013 | Feb. 28, 2013 | Oct. 15, 2012 | Apr. 20, 2012 | Apr. 30, 2009 | Mar. 31, 2013 | May 06, 2013
Common Stock and Dividends |  |  |  |  |  |  |  |
Series A cumulative perpetual preferred shares, outstanding |  |  |  |  |  |  | 216,000 |
Warrants to purchase entity's common stock (in shares) |  |  |  |  |  |  | 1,326,238 |
Warrants, exercise price (in dollars per share) |  |  |  |  |  |  | $ 24.43 |
Percentage of aggregate common stock investment on exercise of warrant to Senior Preferred Stock investment |  |  |  |  |  |  | 15.00% |
Warrants, term |  |  |  |  |  |  | 10 years |
Number of warrants exercised |  |  |  |  |  |  | 0 |
Cash dividends paid to common shareholders (in dollars per share) | $ 0.20 |  |  | $ 0.20 | $ 0.20 |  |  |
Repurchase of common stock, authorized amount |  | $ 40,000,000 | $ 40,000,000 |  |  | $ 40,000,000 |  |
Period of repurchase of common stock |  |  | 12 months |  |  | 12 months |  |
Cumulative number of shares repurchased under all stock repurchase programs |  |  |  |  |  |  |  | 7,843,293
Cumulative cost of shares repurchased under all stock repurchase programs |  |  |  |  |  |  |  | $ 237,536,000

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- Definition The exercise price of each class of warrants or rights outstanding. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(i)(4)) -URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph i -Subparagraph 4 -Article 4 + Details
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