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Derivative Financial Instruments - Narrative (Details) € in Millions, £ in Millions, $ in Millions, $ in Millions | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Mar. 31, 2024 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2020 USD ($) instrument | Mar. 31, 2024 GBP (£) | Mar. 31, 2024 AUD ($) | Mar. 31, 2024 EUR (€) | Dec. 31, 2023 GBP (£) | Dec. 31, 2023 AUD ($) | Dec. 31, 2023 EUR (€)
Derivative [Line Items] |  |  |  |  |  |  |  |  |
Number of instruments terminated | instrument |  |  | 2 |  |  |  |  |  |
Interest expense |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |
Loss to be reclassified in next twelve months |  | $ 13.5 |  |  |  |  |  |  |
Foreign Exchange Forward |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |
Loss to be reclassified in next twelve months |  | $ 0.4 |  |  |  |  |  |  |
Series D and Series E Notes | Senior Notes |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |
Amount of hedged loan |  |  |  | £ 78.0 | $ 197.0 | € 817.5 | £ 78.0 | $ 191.0 | € 817.5
Australian Intercompany Loan | Intercompany Loan Payable | Foreign Exchange Forward |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |
Amount of hedged loan |  |  |  |  | $ 153.5 |  |  | $ 153.5 |
2020 Senior Unsecured Revolving Credit Facility | Credit Facility | Interest Rate Swap | Revolving Credit Facility |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |
Loss to be reclassified in next twelve months | $ 0.5 |  |  |  |  |  |  |  |
Twenty Twenty Senior Unsecured Revolving Credit Facilities | Credit Facility | Revolving Credit Facility |  |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |  |
Payments for settlement of hedge |  |  | $ 16.4 |  |  |  |  |  |
Fee for termination of derivative instruments remaining in accumulated other comprehensive income |  |  | $ 8.7 |  |  |  |  |  |

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- Definition Amount, after tax, of accumulated gain (loss) on derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 11 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482790/220-10-45-11 + Details
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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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