Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

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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.

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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)

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-Name Accounting Standards Codification

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Tier 1 Risk Based Capital as defined in the regulations.

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-Name Accounting Standards Codification

-Topic 942

-SubTopic 505

-Section 50

-Paragraph 1

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Tier 2 risk-based capital as defined in the regulations.

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Common securities proportion to junior subordinated debentures.

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Consecutive quarters of deferred payment

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Debt, Hedge Adjusted Weighted Average Interest Rate

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Number Of Unconsolidated Subsidiary Trusts

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Ownership interest percentage in unconsolidated subsidiary trusts.

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Trust preferred securities proportion to junior subordinated debentures.

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Junior Subordinated Debentures (Narrative) (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Subordinated Borrowing [Line Items]
Percentage ownership interest in subsidiary trusts	100.00%
Number of unconsolidated subsidiary trusts	11
Common securities, approximate percentage of junior subordinated debentures	3.00%
Trust preferred securities, approximate percentage of junior subordinated debentures	97.00%
Junior subordinated debentures	$ 268,566	$ 249,493	$ 249,493
Consecutive quarters of deferred payment	20
Junior Subordinated Debt
Subordinated Borrowing [Line Items]
Debt, weighted average interest rate	2.48%
Debt, Hedge Adjusted Weighted Average Interest Rate	3.13%
Tier One Risk Based Capital	$ 65,100
Tier Two Risk Based Capital	195,400
Cash Flow Hedge of Junior Subordinated Debentures \| Cash Flow Hedging \| Designated as Hedging Instrument \| Interest Rate Swaps and Caps
Subordinated Borrowing [Line Items]
Notional amount	$ 225,000