INVESTMENT BORROWINGS - NARRATIVE (Details) $ in Millions	9 Months Ended
Sep. 30, 2020 USD ($) subsidiary	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Number of insurance subsidiaries that are members of the FHLB \| subsidiary	3
Investment borrowings	$ 1,642.9		$ 1,644.3
Federal Home Loan Bank Advances
Debt Instrument [Line Items]
Federal home loan bank stock	71.0
Investment borrowings	1,642.9
Federal home loan bank, advances, collateral pledged	2,100.0
Aggregate fee to prepay all fixed rate FHLB borrowings	5.2
Interest expense on FHLB borrowings	$ 18.3	$ 36.1

Aggregate Fee to Prepay All Fixed Rate FHLB Borrowings

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- Definition

Interest Expense on FHLB Borrowings

+ References

No definition available.

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- Definition

Amounts borrowed by a wholly owned subsidiary primarily from the Federal Home Loan Bank of Indianapolis; the proceeds of which were used to purchase fixed maturity securities.

+ References

No definition available.

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- Definition

Number Of Insurance Subsidiaries That Are Members Of The Federal Home Loan Bank

+ References

No definition available.

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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

Amount of the collateral pledged in support of federal home loan bank advances outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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- Definition

Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 325
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=75031641&loc=d3e63345-112809

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