Loss Reserves - Reconciliation of Beginning and Ending Balances (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Loss Reserve [Roll Forward]
Reserve at beginning of period	$ 557,988	$ 883,522
Less reinsurance recoverable	28,240	66,905
Net reserve at beginning of period	529,748	816,617
Losses and LAE incurred in respect of delinquency notices received in:
Current year	137,626	104,086
Prior years	(148,948)	(327,512)
Total losses incurred	(11,322)	(223,426)
Losses and LAE paid in respect of delinquency notices received in:
Current year	153	116
Prior years	33,679	36,089
Total losses paid	33,832	36,205
Net reserve at end of period	484,594	556,986
Plus reinsurance recoverable	40,934	46,384
Reserve at end of period	$ 525,528	$ 603,370