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Junior Subordinated Deferrable Interest Debentures (Details) |  |  |  | 12 Months Ended |
--- | --- | --- | --- | --- | ---
Jul. 29, 2015 USD ($) | Dec. 24, 2014 USD ($) | Feb. 11, 2014 USD ($) | Dec. 31, 2015 USD ($) item | Dec. 31, 2014 USD ($)
Junior subordinated deferrable interest debentures, major types of business trusts |  |  |  |  |
Number of statutory business trusts issuing trust preferred securities | item |  |  |  | 6 |
Junior subordinated deferrable interest debentures |  |  |  | $ 161,416,000 | $ 175,416,000
Maximum number of consecutive quarterly period available for deferral of interest payment on Trusts VI, VII, VIII, IX, X, XI and XII | item |  |  |  | 20 |
Percentage of capital securities issued by trust qualifying as Tier I capital, maximum |  |  |  | 25.00% |
Percentage of capital securities issued by trust qualifying as Tier II capital, minimum |  |  |  | 25.00% |
Capital securities issued by the trust, qualifying as Tier I capital |  |  |  | $ 161,416,000 | $ 175,416,000
Trust VI |  |  |  |  |
Junior subordinated deferrable interest debentures, major types of business trusts |  |  |  |  |
Junior subordinated deferrable interest debentures |  |  |  | 25,774,000 |
Trust VII |  |  |  |  |
Junior subordinated deferrable interest debentures, major types of business trusts |  |  |  |  |
Redemption price discount (as a percent) |  |  | 6.00% |  |
Retirement of capital securities |  |  | $ 10,310,000 |  |
Trust VIII |  |  |  |  |
Junior subordinated deferrable interest debentures, major types of business trusts |  |  |  |  |
Junior subordinated deferrable interest debentures |  |  |  | 25,774,000 |
Trust IX |  |  |  |  |
Junior subordinated deferrable interest debentures, major types of business trusts |  |  |  |  |
Junior subordinated deferrable interest debentures |  |  |  | 41,238,000 |
Trust X |  |  |  |  |
Junior subordinated deferrable interest debentures, major types of business trusts |  |  |  |  |
Retirement of capital securities | $ 13,000,000 |  |  |  |
Junior subordinated deferrable interest debentures | 34,021,000 |  |  | $ 21,021,000 |
Trust X and XI |  |  |  |  |
Junior subordinated deferrable interest debentures, major types of business trusts |  |  |  |  |
Redemption price discount (as a percent) |  |  |  | 24.50% |
Trust XI |  |  |  |  |
Junior subordinated deferrable interest debentures, major types of business trusts |  |  |  |  |
Redemption price discount (as a percent) |  | 23.60% |  |  |
Retirement of capital securities | 1,000,000 | $ 5,000,000 |  |  |
Junior subordinated deferrable interest debentures | $ 27,900,000 | $ 32,900,000 |  | $ 26,990,000 |
Trust XII |  |  |  |  |
Junior subordinated deferrable interest debentures, major types of business trusts |  |  |  |  |
Junior subordinated deferrable interest debentures |  |  |  | $ 20,619,000 |

X
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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 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 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 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 SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 9 + Details
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