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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Weighted average interest rate of debt outstanding.

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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=119400593&loc=d3e572229-122910

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-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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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- Definition

Debt Instrument, Interest Payment, Deferral Period

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Debt Instrument, Interest Rate, Stated Percentage Adjusted For Hedge

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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)	6 Months Ended
Junior Subordinated Debentures (Narrative) (Detail)	Jun. 30, 2019 USD ($) trust Rate	Dec. 31, 2018 USD ($)	Jun. 30, 2018 USD ($)
Subordinated Borrowing [Line Items]
Percentage ownership interest in subsidiary trusts	100.00%
Number of unconsolidated subsidiary trusts \| trust	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	$ 253,566,000	$ 253,566,000	$ 253,566,000
Period of deferred payment, not to exceed	60 months
Junior Subordinated Debt
Subordinated Borrowing [Line Items]
Junior subordinated debentures	$ 253,566,000
Weighted average contractual interest rate \| Rate	4.60%
Tier two risk based capital	$ 245,500,000
Interest rate swaps \| Junior Subordinated Debt
Subordinated Borrowing [Line Items]
Derivative notional amount	$ 210,000,000.0
Hedge-adjusted contractual interest rate	4.60%