Derivatives (Tables)

12 Months Ended

Dec. 31, 2023

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Schedule of Derivatives Instruments Statements of Financial Performance and Financial Position, Location

The following table presents the derivative instruments, primary underlying risk exposure, gross notional amount, and estimated fair value of the Company’s derivatives:

		Dec 31, 2023						Dec 31, 2022
(Dollars in Millions)				Estimated Fair Value						Estimated Fair Value
Derivative Instrument	Primary Underlying Risk Exposure	Gross Notional Amount		Assets		Liabilities		Gross Notional Amount		Assets		Liabilities
Derivatives Designated as Hedging Instruments:
Interest Swap Lock	Interest Rate Risk	$	—	$	—	$	—	$	5.0	$	—	$	0.4
Derivatives Not Designated or Not Qualifying as Hedging Instruments:
Treasury Futures	Interest Rate Risk	$	149.7	$	14.7	$	—	$	—	$	—	$	—
Reverse Treasury Lock	Interest Rate Risk	$	—	$	—	$	—	$	100.0	$	1.7	$	—

Derivative Instruments, Gain (Loss)

The below table reflects the amounts of Losses deferred into AOCI and subsequently reclassified into Net Loss through Net Realized Investment Gains for derivatives qualifying as cash flow hedges for the years ended December 31, 2023 and 2022:

	Year Ended
(Dollars in Millions)	Dec 31, 2023		Dec 31, 2022
Amount of Losses Deferred in AOCI	$	—	$	(0.4)
Amount of Losses Reclassified into Income	—		—
Net Comprehensive Loss from Cash Flow Hedges	$	—	$	(0.4)

Schedule of Fair Value Hedging Instruments, Statements of Financial Performance and Financial Position, Location

The below table reflects the effects of changes in the designated hedged asset’s impacts on AOCI and Net Realized Investment Gains as well as the derivative instruments designated as fair value hedges impact on Net Realized Investment Gains for the years ended December 31, 2023 and 2022:

	Year Ended
(Dollars in Millions)	Dec 31, 2023		Dec 31, 2022
Increase in Derivative Instruments Designated as Fair Value Hedges	$	—	$	1.1
Decrease in Fair Value of Hedged Assets Reclassified from AOCI	—		(1.1)
Net Gain from Hedging Activity	$	—	$	—