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Derivative Instruments - Additional information (Details) $ in Millions | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2024 USD ($) agreement | Mar. 31, 2023 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2021 USD ($) agreement | Dec. 31, 2019 USD ($) agreement
Derivative [Line Items] |  |  |  |  |
Interest income, interest-earning asset, increase (decrease) | $ 0.1 |  | $ 0.2 |  |
Interest Rate Contract |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Borrowings at variable interest rates | $ 290.0 |  | 353.0 |  |
Number of interest rate swap agreements | agreement | 3 |  |  |  |
Number of interest rate swaps entered into | agreement |  |  |  | 4 |
Derivative, notional amount |  |  |  | $ 100.0 |
Net fair value of swap asset | $ 15.2 |  | $ 16.5 |  |
Adjustment to interest expense | $ 3.1 | $ 5.4 |  |  |
2021 Swap Agreements, Group 1 |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Number of interest rate swap agreements | agreement | 2 |  |  |  |
2021 Swap Agreements, Group 2 |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Number of interest rate swap agreements | agreement | 2 |  |  |  |
Remaining maturity term | 22 months |  |  |  |
2019 Swap Ageement |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Number of interest rate swap agreements | agreement |  |  |  |  | 1
Derivative, notional amount |  |  |  |  | $ 100.0
Remaining maturity term | 3 months |  |  |  |

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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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480237/815-40-50-5 + Details
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- Definition Nominal or face amount used to calculate payment on derivative. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-1B Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1A -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-1A + Details
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- Definition 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. + References No definition available. + Details
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