Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Deferred tax assets
Net unrealized loss on investments	$ 121,497	$ 0
State income taxes, net of federal impact	58,031	77,637
Goodwill and intangibles	30,782	29,723
Unearned premiums	26,108	23,699
Accrued expenses	11,913	16,584
Lease liability	10,371	11,240
Differences in fair value of financial instruments	5,998	0
Loss reserves	3,102	6,286
Other	32,328	27,932
Total deferred tax assets	300,130	193,101
Deferred tax liabilities
Contingency reserve	587,722	368,000
Depreciation	10,031	12,775
Net unrealized gain on investments	0	31,876
Differences in fair value of financial instruments	0	7,763
Other	23,823	26,768
Total deferred tax liabilities	621,576	447,182
Less: Valuation allowance	69,637	83,428
Net deferred tax asset (liability)	$ (391,083)	$ (337,509)