v2.4.0.6

Shareholders' Equity (Details) (USD $) | 3 Months Ended |  | 0 Months Ended | 3 Months Ended | 1 Months Ended | 3 Months Ended |  |  | 1 Months Ended | 3 Months Ended |  | 3 Months Ended
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Mar. 31, 2013 period director | Mar. 31, 2012 | Dec. 31, 2012 | Mar. 15, 2013 Common Stock [Member] | Feb. 20, 2013 Common Stock [Member] | Mar. 15, 2012 Common Stock [Member] | Mar. 31, 2013 Common Stock [Member] | Dec. 31, 2006 Series D Preferred Stock [Member] | Mar. 31, 2013 Series D Preferred Stock [Member] | Dec. 27, 2012 Series D Preferred Stock [Member] | Nov. 30, 2011 Series D Preferred Stock [Member] | Mar. 31, 2004 Series C Preferred Stock [Member] | Mar. 31, 2013 Series C Preferred Stock [Member] | Mar. 23, 2009 Series C Preferred Stock [Member] | Mar. 31, 2013 Retained Earnings [Member] | Mar. 31, 2012 Retained Earnings [Member]
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends declared, Per common share (usd per share) | $ 0.28 | $ 0.27 |  | $ 0.28 |  |  |  |  |  |  |  |  |  |  |  |
Dividends paid, Per common share (usd per share) |  |  |  |  |  | $ 0.28 |  |  |  |  |  |  |  |  |  |
Dividends declared and paid, Preference shares | $ 6,275,000 | $ 8,750,000 |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 8,750,000
Dividends, Common Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 12,329,000 | 13,886,000
Repurchase of shares |  |  |  |  |  |  | 1,400,000 |  |  |  |  |  |  |  |  |
Common shares repurchased during period, Aggregate value |  |  |  |  |  |  | (111,300,000) |  |  |  |  |  |  |  |  |
Common shares repurchased during period, Average cost per share |  |  |  |  |  |  | $ 81.29 |  |  |  |  |  |  |  |  |
Share repurchase program, Authorized aggregate amount |  |  |  |  | 500,000,000 |  |  |  |  |  |  |  |  |  |  |
Share repurchase program, Remaining authorized aggregate amount |  |  |  |  |  |  | 500,000,000 |  |  |  |  |  |  |  |  |
Proceeds from issuance of preference shares |  |  |  |  |  |  |  | 300,000,000 |  |  |  | 250,000,000 |  |  |  |
Preference shares issued, Shares |  |  |  |  |  |  |  | 12,000,000 |  |  |  | 10,000,000 |  |  |  |
Equity Issuance, Per Share Amount |  |  |  |  |  |  |  | $ 25 |  |  |  | $ 25 |  |  |  |
Preferred Stock, Redemption Price Per Share |  |  |  |  |  |  |  |  |  |  | $ 25 |  |  | $ 25 |  |
Preference shares, Dividend rate |  |  |  |  |  |  |  |  | 6.60% |  |  |  | 6.08% |  |  |
Preferred shares, Amount of preferred dividends in arrears, equivalent number of periods, trigger | 6 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred shares, Preferred stock dividends in arrears, triggered shareholder election right, number of directors | 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred shares, Redemption amount, shares |  |  |  |  |  |  |  |  |  | 6,000,000 |  |  |  |  |  |
Preferred shares, Redemption mount |  |  |  |  |  |  |  |  |  | $ 150,000,000 |  |  |  |  |  |
Preferred shares, Shares outstanding | 16,000,000 |  | 16,000,000 |  |  |  |  |  |  | 6,000,000 |  |  |  |  |  |

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- Definition Equity impact of aggregate cash, stock, and paid-in-kind dividends declared for preferred shareholders during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 01-6 -Paragraph 14 -Subparagraph l -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. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 3: 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 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 405 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817 + Details
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