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

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- Definition

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

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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.

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No definition available.

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- Definition

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

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- Definition

The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

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- Definition

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

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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.

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Subordinated Notes (Details) - USD ($)	12 Months Ended
Subordinated Notes (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2014
Debt Instrument [Line Items]
Outstanding subordinated notes	$ 436,095,000	$ 139,210,000
Proceeds, net of underwriting discount	296,617,000	$ 0	$ 0
Costs incurred in connection with the issuance of subordinated notes	3,300,000			$ 1,300,000
4.85% subordinated notes maturing in June 2029
Debt Instrument [Line Items]
Proceeds, net of underwriting discount	296,700,000
5.00% subordinated notes maturing in June 2029
Debt Instrument [Line Items]
Proceeds, net of underwriting discount				139,100,000
Subordinated debt
Debt Instrument [Line Items]
Unamortized balances of costs for issuance of subordinated notes	3,900,000
Subordinated debt \| 4.85% subordinated notes maturing in June 2029
Debt Instrument [Line Items]
Debt instrument, face amount	$ 300,000,000.0
Stated interest rate	4.85%
Subordinated debt \| 5.00% subordinated notes maturing in June 2029
Debt Instrument [Line Items]
Debt instrument, face amount				$ 140,000,000.0
Stated interest rate				5.00%