Loss Reserves - Reconciliation of Beginning and Ending Balances (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Loss Reserve [Roll Forward]
Reserve at beginning of period	$ 674,019	$ 985,635
Less reinsurance recoverable	33,328	48,474
Net reserve at beginning of period	640,691	937,161
Losses and LAE incurred in respect of delinquency notices received in:
Current year	94,063	108,361
Prior years	(33,164)	(97,966)
Total losses incurred	60,899	10,395
Losses and LAE paid in respect of delinquency notices received in:
Current year	2,650	263
Prior years	109,420	173,313
Reinsurance terminations	(13,980)	(1,984)
Total losses paid	98,090	171,592
Net reserve at end of period	603,500	775,964
Plus reinsurance recoverables	18,402	37,051
Reserve at end of period	$ 621,902	$ 813,015