Summary of Significant Accounting Policies - Narrative (Details) $ in Thousands	12 Months Ended
Dec. 31, 2024 USD ($) Segment	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Loss contract reserves	$ 4,900	$ 0
Certificates of deposit	$ 5,500	6,700
Number of operating segments \| Segment	1
Number of reportable segments \| Segment	1
General and administrative	$ 268,912	285,760	$ 207,789
Reportable Segment
Summary Of Significant Accounting Policies [Line Items]
Other segment items	95,500	168,800	90,800
Platform Support Costs \| Reportable Segment
Summary Of Significant Accounting Policies [Line Items]
General and administrative	$ 169,400	$ 163,700	$ 127,500
Minimum
Summary Of Significant Accounting Policies [Line Items]
Useful Life (Years)	1 year
Maximum
Summary Of Significant Accounting Policies [Line Items]
Useful Life (Years)	30 years

Summary of significant accounting policies.

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A savings certificate entitling the Entity (that is, bearer) to receive interest at an established maturity date, based upon a fixed interest rate. A certificate of deposit may be issued in any denomination. Certificates of deposit are generally issued by commercial banks and, therefore, insured by the FDIC (up to the prescribed limit). Certificates of deposit generally restrict holders from withdrawing funds on demand without the incurrence of penalties. Generally, only certificates of deposit with original maturities of three months or less qualify as cash equivalents. Original maturity means original maturity to the entity holding the investment. As a related example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

+ References

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Cumulative provision for contract losses not offset against related costs accumulated on the balance sheet.

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Amount of other expense (income) and loss (gain) calculated as difference between segment revenue and separately disclosed expense category to arrive at segment profit (loss).

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