Finance Receivables - Contractual Maturities Of Finance Receivables (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
2020	$ 2,315,528
2021	1,241,305
2022	1,385,777
2023	1,547,775
2024	1,077,800
Thereafter	4,762
Total finance receivables	7,572,947	$ 7,411,816	$ 7,157,557	$ 7,008,801	$ 7,015,331
United States
Accounts, Notes, Loans and Financing Receivable [Line Items]
2020	2,177,277
2021	1,188,915
2022	1,329,148
2023	1,486,564
2024	1,061,450
Thereafter	4,762
Total finance receivables	7,248,116
Canada
Accounts, Notes, Loans and Financing Receivable [Line Items]
2020	138,251
2021	52,390
2022	56,629
2023	61,211
2024	16,350
Thereafter	0
Total finance receivables	$ 324,831