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Consolidated Statements Of Changes In Shareholders' Equity (Parenthetical) - $ / shares | 12 Months Ended
--- | ---
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Common stock dividends per share, declared | $ 0.80 | $ 0.77 | $ 0.74
Series A 3% Preferred Stock [Member] |  |  |
Preferred stock dividends per share, declared | $ 3.00 | $ 3.00 | 3.00
Preferred stock, dividend percentage | 3.00% | 3.00% |
Series B-1 8.48% Preferred Stock [Member] |  |  |
Preferred stock dividends per share, declared | $ 8.48 | $ 8.48 | $ 8.48
Preferred stock, dividend percentage | 8.48% | 8.48% |

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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 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=27012166&loc=d3e187085-122770 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 + Details
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