Loss Reserves - Default Inventory Reconciliation (Details) - loan	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Primary Default Inventory [Roll Forward]
Beginning delinquent inventory	30,028	32,898	46,556
New Notices	106,099	54,239	54,448
Cures	(76,107)	(52,035)	(60,511)
Paid claims	(2,245)	(4,267)	(5,750)
Rescissions and denials	(65)	(168)	(267)
Other items removed from inventory	0	(639)	(1,578)
Ending delinquent inventory	57,710	30,028	32,898