Related Party Transactions - Narrative (Details) $ in Millions	12 Months Ended
Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Related Party Transaction [Line Items]
Plus component of annual investment management fee	0.25
Annual fee cap	0.15
Asset Management Arrangement
Related Party Transaction [Line Items]
Related party fees	$ 5.8	$ 5.3
Related party fees still due	3.2	2.1
Management Consulting Agreement
Related Party Transaction [Line Items]
Related party fees	5.0	5.0
Related party fees still due	0.0	0.0
Beneficial owner
Related Party Transaction [Line Items]
Intercompany balance payable	$ 0.6	$ 18.1
Maximum
Related Party Transaction [Line Items]
Percentage of consolidated group's net income due to Apollo Management	1.00%
Fees due to Apollo Management	$ 5.0

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Related Party Transaction, Rate of Interest

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Amount for accounts payable to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amounts due from owners or owners with a beneficial interest of more than 10 percent of the voting interests or officers of the company, which are usually due within 1 year (or 1 business cycle).

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Amount of payable due to an entity that is affiliated with the reporting entity by means of direct or indirect ownership. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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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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Identify the stated interest rate per the agreement, for example, leasing and debt arrangements between related parties.

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