Basis of Presentation and Significant Accounting Policies Noncontrolling Interest (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Stockholders' Equity Attributable to Noncontrolling Interest	$ 197,755	$ 52,958
Preferred stock, shares outstanding (in shares)	0	0
Dividend Rate on Auction Rate Preferred Shares	11.448%
Redeemable Noncontrolling Interest, Equity, Carrying Amount	$ 140,860	$ 17,079	$ 19,983
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value	185,469	2,450
Net Income (Loss) Attributable to Redeemable Noncontrolling Interest	(1,282)	1,318
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	(2,391)	(1,880)
Temporary Equity, Accretion to Redemption Value, Adjustment	(53,210)	$ (4,792)
Foreign exchange	(4,805)
Insurance Distribution
Stockholders' Equity Attributable to Noncontrolling Interest	$ 146,837
Riverton
Ownership percentage	80.00%
Beat
Ownership percentage	60.00%
Ambac Assurance Corporation
Stockholders' Equity Attributable to Noncontrolling Interest	$ 50,918
Preferred stock, shares outstanding (in shares)	4,596	4,596
Preferred stock, liquidation preference, value	$ 114,900	$ 114,900
Beat \| Minimum [Member] \| Beat
Ownership percentage	60.00%
Subsidiary, Ownership Percentage, Parent	36.00%
Beat \| Maximum [Member] \| Beat
Ownership percentage	100.00%
Subsidiary, Ownership Percentage, Parent	60.00%

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Noncontrolling Interest, Increase (Decrease) From Foreign Exchange

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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This element represents the fair value of the noncontrolling interest in the acquiree at the acquisition date.

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Amount of equity (deficit) attributable to noncontrolling interest. Excludes temporary equity.

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Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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Amount of Net Income (Loss) attributable to redeemable noncontrolling interest.

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Value of the difference between preference in liquidation and the par or stated values of the preferred shares.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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As of the reporting date, the aggregate carrying amount of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

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Amount of decrease to net income for accretion of temporary equity to its redemption value to derive net income apportioned to common stockholders.

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