Debt Instrument, Covenant, Actual Aggregate Total Adjusted Capital To Company Action Level Risk-Based Capital Ratio

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- Definition

Debt Instrument, Covenant, Actual Consolidated Net Worth, Amount

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- Definition

Debt Instrument, Covenant, Actual Debt To Total Capitalization Ratio

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- Definition

Debt Instrument, Covenant, Maximum Required Debt To Total Capitalization Ratio

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Debt Instrument, Covenant, Minimum Required Aggregate Total Adjusted Capital To Company Action Level Risk-Based Capital Ratio

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- Definition

Debt Instrument, Covenant, Required Minimum Consolidated Net Worth, Amount

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Debt Instrument, Covenant, Required Minimum Consolidated Net Worth, Component One, Amount

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Debt Instrument, Covenant, Required Minimum Net Worth, Component Two, Percent Of Net Equity Proceeds Received From Issuance And Sale Of Equity Interests

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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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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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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NOTES PAYABLE - DIRECT CORPORATE OBLIGATIONS - NARRATIVE (Details) - USD ($)	Oct. 13, 2017	May 19, 2015	Jun. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Outstanding amount			$ 989,700,000	$ 989,100,000
Line of Credit \| Revolving Credit Agreement
Debt Instrument [Line Items]
Line of credit maximum borrowing capacity	$ 250,000,000.0	$ 150,000,000.0
Debt instrument, term		4 years
Initial drawing amount		$ 100,000,000.0
Remaining borrowing capacity	$ 100,000,000.0	50,000,000.0
Outstanding amount			$ 0
Debt covenant, required minimum debt to total capitalization ratio	35.00%
Debt covenant, actual debt to total capitalization ratio at period end			23.80%
Debt covenant, minimum required aggregate total adjusted capital to company action level risk-based capital ratio	250.00%
Debt covenant, actual aggregate total adjusted capital to company action level risk-based capital ratio at period end			405.00%
Debt covenant, minimum required consolidated net worth, component one, amount		$ 2,674,000,000
Debt covenant, minimum required consolidated net worth, component two, as a percent of net equity proceeds received from issuance and sale of equity interests	50.00%
Debt covenant, actual consolidated net worth at period end			$ 3,211,000,000.0
Debt covenant, required minimum consolidated net worth, amount			$ 2,693,200,000
Line of Credit \| Revolving Credit Agreement \| Federal Funds Rate
Debt Instrument [Line Items]
Basis spread on variable rate	0.50%
Line of Credit \| Revolving Credit Agreement \| Eurodollar \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	1.375%
Line of Credit \| Revolving Credit Agreement \| Eurodollar \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	2.125%
Line of Credit \| Revolving Credit Agreement \| Base Rate \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	0.375%
Line of Credit \| Revolving Credit Agreement \| Base Rate \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	1.125%