Amount of advances or credit lines used from the Federal Home Loan Bank (FHLB).

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- Definition

Number of unconsolidated subsidiary trusts owned by the company.

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Percentage of common equity of each unconsolidated subsidiary trust owned by the company.

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No definition available.

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- Definition

Number of months of interest that would be forfeited if a subordinated note is redeemed by the holder prior to the stated maturity date.

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No definition available.

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Written Notice For Holder

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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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- Definition

States the interest rate applicable to Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
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- Definition

Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Amount of cash outflow for the payment of debt classified as other, maturing after one year or the operating cycle, if longer.

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The cash outflow from the repayment of long-term borrowing where a lender is placed in a lien position behind debt having a higher priority of repayment (senior) in case of liquidation of the entity's assets or underlying collateral.

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Long-Term Borrowings - Additional Information (Detail) $ in Millions	3 Months Ended	6 Months Ended	12 Months Ended
	Jun. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Dec. 31, 2019 USD ($) Trust	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Debt Instrument [Line Items]
Number of unconsolidated subsidiary trusts \| Trust			3
Percent of the common equity of each Trust owned by the Corporation			100.00%
Repayments of long-term debt			$ 239.0	$ 77.0	$ 199.0
Repayments of subordinated debt	$ 9.5
Repayments of other long-term debt		$ 15.5
FHLB
Debt Instrument [Line Items]
Credit available with FHLB			7,900.0
Credit with FHLB used			$ 3,200.0
Subordinated Notes
Debt Instrument [Line Items]
Written notice for holder			30 days
Minimum \| FHLB
Debt Instrument [Line Items]
Effective interest rates			1.62%	1.39%
Minimum \| Subordinated Notes
Debt Instrument [Line Items]
Months prior to maturity, interest discount			3 months
Maximum \| FHLB
Debt Instrument [Line Items]
Effective interest rates			2.71%	4.19%
Maximum \| Subordinated Notes
Debt Instrument [Line Items]
Months prior to maturity, interest discount			12 months
Trust Preferred Securities
Debt Instrument [Line Items]
Repayments of long-term debt		$ 44.0