CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Cash flows from operating activities:
Net Loss	$ (165.5)	$ (202.2)	$ (236.9)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	15.2	20.0	20.0
Stock-based compensation	61.3	64.5	59.9
Amortization of bond discount	(5.8)	(6.1)	(2.6)
Provision for bad debt	22.1	11.0	8.1
Gain on early lease termination	(2.3)	0.0	0.0
Asset impairment charge	0.0	0.3	3.7
Changes in operating assets and liabilities:
Premium receivable	(123.2)	(90.2)	(50.5)
Reinsurance recoverable	17.0	(32.0)	18.4
Prepaid reinsurance premium	105.7	(57.3)	(31.8)
Deferred acquisition costs	0.1	(3.4)	(1.9)
Other assets	(8.2)	21.2	8.9
Unpaid losses and loss adjustment expenses	5.0	35.8	6.1
Unearned premium	122.0	101.3	65.7
Trade payables	(4.0)	3.9	(0.5)
Funds held for reinsurance treaties	(50.1)	90.8	(7.2)
Deferred ceding commission	(27.4)	24.2	1.7
Ceded premium payable	0.1	0.6	4.8
Other liabilities and accrued expenses	21.5	6.2	15.0
Net cash used in operating activities	(16.5)	(11.4)	(119.1)
Cash flows from investing activities:
Proceeds from short-term investments sold or matured	41.6	77.5	143.5
Proceeds from bonds sold or matured	383.1	336.3	349.6
Cost of short-term investments acquired	(27.7)	(58.1)	(71.5)
Cost of bonds acquired	(476.7)	(305.7)	(323.7)
Purchases of property and equipment	(9.4)	(9.4)	(9.2)
Net cash (used in) provided by investing activities	(89.1)	40.6	88.7
Cash flows from financing activities:
Proceeds from borrowings under financing agreement	133.0	96.1	19.1
Payment on borrowings under financing agreement	(58.3)	(27.7)	(4.2)
Proceeds from stock exercises	31.9	19.3	0.5
Net cash provided by financing activities	106.6	87.7	15.4
Effect of exchange rate changes on cash, cash equivalents and restricted cash	10.1	(2.7)	0.0
Net increase (decrease) in cash, cash equivalents and restricted cash	11.1	114.2	(15.0)
Cash, cash equivalents and restricted cash at beginning of year	385.7	271.5	286.5
Cash, cash equivalents and restricted cash at end of year	396.8	385.7	271.5
Supplemental disclosure of cash flow information:
Cash paid for income taxes	2.5	2.5	0.7
Cash paid for interest expense on borrowings under financing agreement	16.3	5.0	0.3
Non-cash transactions:
Right-of-use assets derecognized due to lease modification	$ 3.1	$ 0.0	$ 0.0