Fair value of the assets less the liabilities of a derivative or group of derivatives.

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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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Nominal or face amount used to calculate payment on derivative.

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Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of increase (decrease) in interest income on interest-earning asset.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Number of interest rate derivative instruments held by the entity at the reporting date.

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Adjustment to Interest Expense

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Derivative Instruments - Additional information (Details) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2021 USD ($) agreement	Dec. 31, 2023 USD ($) agreement	Dec. 31, 2022 USD ($)	Dec. 31, 2019 USD ($) agreement
Derivative instruments
Interest income, interest-earning asset, increase (decrease)		$ 0.2
Interest rate contracts
Derivative instruments
Borrowings at variable interest rates		$ 353.0	$ 727.0
Number of interest rate swap agreements \| agreement		5
Number of interest rate derivatives entered into \| agreement	4
Notional amount outstanding	$ 100.0
Net fair value of swap asset (liability)		$ 16.5	34.8
Adjustment to interest expense		$ (23.4)	(7.8)
Derivative, accumulated gain (loss), net			$ 34.8
2021 Swap Agreements, Group 1
Derivative instruments
Number of interest rate swap agreements \| agreement		2
Remaining maturity term		1 month
2021 Swap Agreements, Group 2
Derivative instruments
Number of interest rate swap agreements \| agreement		2
Remaining maturity term		25 months
2019 Swap Ageement
Derivative instruments
Number of interest rate swap agreements \| agreement				1
Notional amount outstanding				$ 100.0
Remaining maturity term		6 months