Loss Reserves - Delinquent Items (Details) - loan	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021
Aging of the Primary Delinquent Inventory [Abstract]
3 months or less (in loans)	7,663		8,820	6,791
4 - 11 months (in loans)	8,070		8,217	7,946
12 months or more (in loans)	8,090		9,350	12,118
Total primary delinquent inventory (in loans)	23,823	24,757	26,387	26,855	30,462	33,290
3 months or less (as a percent)	32.00%		33.00%	25.00%
4 - 11 months (as a percent)	34.00%		31.00%	30.00%
12 months or more (as a percent)	34.00%		36.00%	45.00%
Total primary delinquent inventory (as a percent)	100.00%		100.00%	100.00%
Primary claims received inventory included in ending delinquent inventory (in loans)	291		267	254
Percent of 12 months or more delinquent inventory, delinquent for more than 36 months (as a percent)	41.00%		36.00%	29.00%