INVESTMENTS - Additional Information (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Gain (Loss) on Securities [Line Items]
Proceeds from Sale of Debt Securities, Available-for-sale	$ 219.7	$ 11.4	$ 271.8	$ 41.3
Available-for-sale Securities, Gross Realized Gains	$ 2.5	0.1	3.1	0.1
Available-for-sale Securities, Gross Realized Losses		$ 0.1	$ 3.5	$ 0.1
NumberOfSecuritiesInSecurityPortfolio	1,416		1,416		1,351
NumberOfSecuritiesInUnrealizedLossPosition	200		200		94
Debt Securities, Held-to-maturity, Nonaccrual	$ 0.0		$ 0.0		$ 0.0
Debt Securities, Held-to-maturity, Allowance for Credit Loss	$ 0.0		$ 0.0		$ 0.0

The total number of securities included in the investment securities portfolio.

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The total number of securities included in the investment securities portfolio that include net accumulated unrealized losses.

+ References

No definition available.

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- Definition

This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

No definition available.

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This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

No definition available.

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- Definition

Amount of allowance for credit loss for debt security measured at amortized cost (held-to-maturity).

+ References

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- Definition

Amount of investment in debt security measured at amortized cost (held-to-maturity) on nonaccrual status.

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Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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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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