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Common Stock and Dividends (Details) - USD ($) |  |  |  | 6 Months Ended
--- | --- | --- | --- | ---
Aug. 02, 2016 | Apr. 18, 2016 | Apr. 09, 2016 | Jun. 30, 2016
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
Cash dividends (as a percent) |  |  |  | 0.33%
Cash dividends paid to common shareholders (in dollars per share) |  | $ 0.29 |  |
Repurchase of common stock, authorized amount |  |  | $ 40,000,000 | $ 40,000,000
Period of repurchase of common stock |  |  | 12 months |
Cumulative number of shares repurchased under all stock repurchase programs | 9,240,629 |  |  |
Cumulative cost of shares repurchased under all stock repurchase programs | $ 271,096,000 |  |  |

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- Definition Exercise price per share or per unit 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=26873400&loc=d3e23780-122690 + Details
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