Face (par) amount of debt instrument at time of issuance.

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Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

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.

+ References

No definition available.

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- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

+ References

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Qualifying Debt Subordinated Debt Details (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018	Jun. 16, 2016	Jun. 29, 2015
Debt Instrument [Line Items]
Subordinated Debt	$ 319,200,000	$ 299,400,000
Subordinated Debt [Member] \| Subordinated Debentures Maturing July 2056 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 175,000,000.0		$ 175,000,000.0
Debt Issuance Cost			$ 5,500,000
Debt Instrument, Interest Rate, Stated Percentage			6.25%
Subordinated Debt [Member] \| Subordinated Debentures Maturing July 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount				$ 150,000,000.0
Debt Issuance Cost				$ 1,800,000
Debt Instrument, Interest Rate, Stated Percentage	5.00%