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Junior Subordinated Interest Deferrable Debentures (Details) (USD $) | 12 Months Ended |  | 1 Months Ended |
--- | --- | --- | --- | ---
Dec. 31, 2011 quarter trust | Dec. 31, 2010 | Jul. 31, 2011 Trust I | Jun. 30, 2011 Trust I | Mar. 31, 2011 Trust I | Mar. 14, 2011 Trust I
Junior Subordinated Deferrable Interest Debentures |  |  |  |  |  |
Number of statutory business trusts issuing trust preferred securities | 8 |  |  |  |  |
Junior subordinated deferrable interest debentures | $ 190,726,000 | $ 201,117,000 |  |  |  |
Maximum number of consecutive quarterly period available for deferral of interest payment on Trusts VI, VII, VIII, IX, X, XI and XII | 20 |  |  |  |  |
Percentage of capital securities issued by trust qualifying as Tier I capital, maximum | 25.00% |  |  |  |  |
Capital securities issued by the trust, qualifying as Tier I capital | 190,726,000 | 201,117,000 |  |  |  |
Junior subordinated deferrable interest debentures, major types of business trusts |  |  |  |  |  |
Consented amount to repurchase shares |  |  |  |  | 10,400,000 |
Treasury stock repurchased | $ 256,793,000 | $ 250,358,000 |  |  |  | $ 11,000,000
Originally permitted semi-annual cash dividend (in dollars per share) |  |  |  |  |  | $ 0.33
Securities redeemed |  |  | One half | One half |  |

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- Definition Represents the maximum number of consecutive quarterly periods available to the entity for deferring the payment of interest on Trusts VI, VII, VIII, IX, X, XI and XII. + References No definition available. + Details
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- Definition The per share amount of a dividend declared, but not paid, as of the financial reporting date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 32 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586 + Details
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- Definition Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 9 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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- Definition The amount allocated to treasury stock. Treasury stock is common and preferred shares of an entity that were issued, repurchased by the entity, and are held in its treasury. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Technical Bulletin (FTB) -Number 85-6 -Paragraph 3 -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 FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6405834&loc=d3e23315-112656 + Details
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