Related party transactions - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Related Party Transaction [Line Items]
Investment expenses and fees	$ 2,038	$ 1,690
Payments for repurchase of common stock	65,283	49,724
Asset, held-in-Trust	200,900		$ 141,900
Cash and Cash Equivalents
Related Party Transaction [Line Items]
Asset, held-in-Trust	27,500		$ 6,300
Related Party
Related Party Transaction [Line Items]
General and administrative expense	2,300	2,800
Investment expenses and fees	1,800	1,500
Cash paid to Genworth	22,800	20,800
Payments for repurchase of common stock	$ 53,000	$ 39,900

The total amount of cash and securities held by third party trustees pursuant to terms of debt instruments or other agreements as of the date of each statement of financial position presented, which can be used by the trustee only to pay the noncurrent portion of specified obligations.

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Amount of paid and unpaid cash dividends declared for classes of stock, for example, but not limited to, common and preferred.

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The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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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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