Loss Reserves - Default Inventory Reconciliation (Details) - loan	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Primary Default Inventory [Roll Forward]
Beginning delinquent inventory	32,898	46,556	50,282
New Notices	54,239	54,448	68,268
Cures	(52,035)	(60,511)	(61,094)
Paid claims	(4,267)	(5,750)	(9,206)
Rescissions and denials	(168)	(267)	(357)
Other items removed from inventory	(639)	(1,578)	(1,337)
Ending delinquent inventory	30,028	32,898	46,556