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Stockholders' Equity - Performance-Based Restricted Stock Units (Narrative) (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2025	Dec. 31, 2024	Dec. 31, 2022
Stockholders' Equity Capital Structure [Line Items]
Earnout target percentage (as a percent)		0.00%
Actual total shareholder return (as a percent)		(47.25%)
Relative total shareholder return ranking (as a percent)		3.70%
Market-Based PRSUs
Stockholders' Equity Capital Structure [Line Items]
Equity instruments granted (in shares)	324,165
Equity instruments granted, weighted average grant date fair value	$ 15.0
Earnout target percentage (as a percent)		0.00%
Relative total shareholder return ranking (as a percent)		1.50%
PRSUs
Stockholders' Equity Capital Structure [Line Items]
Earnout target percentage (as a percent)		0.00%
Term of the performance period (in years)	1 year
Relative total shareholder return ranking (as a percent)			2.90%
PRSUs | Tranche One
Stockholders' Equity Capital Structure [Line Items]
Award vesting percentage	33.33%
PRSUs | Tranche Two
Stockholders' Equity Capital Structure [Line Items]
Award vesting percentage	66.67%
PRSUs | Minimum
Stockholders' Equity Capital Structure [Line Items]
Earnout target percentage (as a percent)	0
PRSUs | Maximum
Stockholders' Equity Capital Structure [Line Items]
Earnout target percentage (as a percent)	2
PRSUs | Maximum | Executive Employment Terminates due to Death by end of 2024
Stockholders' Equity Capital Structure [Line Items]
Earnout target percentage (as a percent)	1
PRSUs | Maximum | Executive Employment Terminates due to Disability by end of 2024
Stockholders' Equity Capital Structure [Line Items]
Earnout target percentage (as a percent)	0.50
PRSUs | Maximum | Shareholder for Performance Any Period is Negative
Stockholders' Equity Capital Structure [Line Items]
Earnout target percentage (as a percent)	1

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(01)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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