Loss Reserves - Reconciliation of Beginning and Ending Balances (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Loss Reserve [Roll Forward]
Reserve at beginning of period	$ 555,334	$ 674,019
Less reinsurance recoverable	21,641	33,328
Net reserve at beginning of period	533,693	640,691
Losses and LAE incurred in respect of delinquency notices received in:
Current year	59,799	47,488
Prior years	1,157	(8,425)
Total losses incurred	60,956	39,063
Losses and LAE paid in respect of delinquency notices received in:
Current year	39	0
Prior years	45,633	56,365
Reinsurance terminations	(20)	0
Total losses paid	45,652	56,365
Net reserve at end of period	548,997	623,389
Plus reinsurance recoverables	25,756	31,875
Reserve at end of period	$ 574,753	$ 655,264